Pete Alonso reached his 300th home run against his former club, and Citi Field gave him an extraordinary moment
Pete Alonso returned to the place where he built the largest part of his MLB career and there reached one of the most important individual milestones in baseball. The Baltimore Orioles first baseman hit the 300th home run of his career on September 15 at Citi Field, the stadium of the New York Mets, for whom he played his first seven seasons in the world's strongest baseball league. In the ninth inning, with Baltimore trailing 3-2, Alonso sent a pitch from right-handed pitcher Kodai Senga over the fence in left-center field to tie the score. According to official MLB data, it was his 36th home run of the 2026 season and the first of his 300 total that he had hit at Citi Field as a visiting player. Even more unusual than the milestone itself was the response from the stands: Mets fans loudly celebrated the hit against their own team and called their former favorite out for a rare curtain call from the visiting dugout.
Baltimore eventually won 7-5 after 11 innings, so Alonso's historic hit was not merely a symbolic moment marking his return to New York but directly changed the course of the game. MLB's official record shows that after tying the game in the ninth, the Orioles took the lead in the 10th, the Mets responded to make it 4-4, and the decision came in the 11th inning when Coby Mayo hit a three-run inside-the-park home run for a 7-4 lead. New York got one run back in the bottom half of the inning, but Andrew Kittredge closed out the game. The victory was also important for Baltimore in the context of the final stretch of the regular season: after that game, the Orioles had a 74-78 record and, according to MLB, were three games behind the Cleveland Guardians in the race for the third American League Wild Card spot, with 10 games remaining on the schedule.
Ninth-inning home run changed the entire evening
The Mets entered the final stage of the game with a narrow 3-2 lead. Baltimore scored both of its early runs on solo home runs by Christian Encarnacion-Strand and Jeremiah Jackson in the second inning, while New York responded with runs from Jared Young, Juan Soto and Carson Benge. The score then remained unchanged until the top of the ninth inning, when Alonso came to bat against Senga. According to MLB Statcast, with a two-ball, no-strike count, Senga threw him an 82.5 mph forkball, or about 133 kilometers per hour. Alonso hit the ball with an exit velocity of 109.6 mph, approximately 176 kilometers per hour, at a launch angle of 35 degrees, and the estimated distance of the flight was about 413 feet, or 126 meters.
The ball landed beyond the fence in left-center field, and the scoreboard changed to 3-3. After the hit, Alonso forcefully tossed his bat toward the Orioles' bench and began rounding the bases, while the crowd's reaction increasingly resembled anything but the usual atmosphere following an opposing team's home run. MLB states that the ovation grew louder as he rounded the bases, and after he returned to the dugout his teammates encouraged him to step back out in front of the crowd. Alonso then came out onto the steps of the visiting dugout and raised his cap toward the stands. Baltimore manager Craig Albernaz later emphasized how unusual it was to see a curtain call for a player wearing the visiting uniform, while Senga said through an interpreter that the noise after the hit was so loud that he could not clearly hear the PitchCom communication system.
That kind of treatment from the crowd toward an opposing player has a clear background. From his debut in 2019 through the end of the 2025 season, Alonso played 1,008 games for the Mets and became the franchise's all-time home run leader. He finished his tenure with the Queens club with 264 home runs, surpassing Darryl Strawberry, who had held the record for decades with 252. When Alonso passed Strawberry in 2025, he also received a huge curtain call at Citi Field, at the time still wearing a Mets uniform. A year later, the same crowd rose to its feet again because of one of his home runs, but this time the hit tied the game in Baltimore's favor.
Return to Queens began with ovations the day before
Alonso's 300th home run came in his second game at Citi Field as a visiting player. According to MLB, he first returned to the stadium in an Orioles uniform on September 14, after leaving the Mets the previous winter and signing a five-year, $155 million contract with Baltimore. Fans were already applauding him and chanting his name during batting practice, and before the first game a video was shown honoring his years in New York. The ovation continued when he came to bat for the first time as an opponent. Alonso later said that he appreciated the years of support and that returning to the stadium where he had spent a large part of his professional life was special.
He remained without a home run in that first game of the series, even though he had arrived in New York with 299. The Orioles won 2-1, meaning Alonso entered the next game just one swing away from the milestone. The historic moment came the following night, in a situation where Baltimore needed not only a personal record from its most prominent power hitter but also a hit to stay in the game. That is precisely why the 300th home run carried double significance: it was a personal milestone and a game-tying hit in the ninth inning. After the game, Alonso emphasized that it mattered more to him that the team had won during a stretch in which it was still trying to reach the postseason.
The number 300 carries additional significance for him because of the pace at which he reached it. According to data cited by MLB from the Elias Sports Bureau, Alonso became the 19th active MLB player with at least 300 home runs. He also became the 20th player in American and National League history to hit his 300th home run against a former club. MLB also notes that only Ralph Kiner, with 329, and Albert Pujols, with 319 home runs, had more such hits than Alonso through their first eight seasons in the league. That places him in a very small historical group of players who maintained an exceptionally high rate of power hitting from the beginning of their careers.
From a record-setting rookie season to the Mets' all-time home run leader
Alonso's reputation as one of the most dangerous power hitters of his generation was built practically as soon as he entered MLB. In his 2019 rookie season, he hit 53 home runs, which at the time was the league record for a rookie, while also leading all of MLB in that category. Major League Baseball states that with that performance he broke Aaron Judge's previous rookie record of 52 home runs. Alonso also won the Jackie Robinson National League Rookie of the Year Award that year, receiving 29 of 30 first-place votes according to MLB's official announcement. Even then, he became a central figure in the Mets' offense and one of the most recognizable hitters in New York.
His rise to the top of the club's leaderboard took six additional seasons. In August 2025, he reached 253 home runs in a Mets uniform and thereby passed Strawberry, whose record of 252 had stood for 37 years. By the end of that season, Alonso had extended the club record to 264. The Mets' official MLB statistics still list him first on the franchise's all-time leaderboard, ahead of Strawberry with 252, David Wright with 242 and Mike Piazza with 220 home runs for the club. When the 36 home runs he had hit by September 15, 2026, in his first season with Baltimore are added, the total reaches an even 300 for his career.
The move to Baltimore therefore was not merely a standard club change by a well-known veteran. In December 2025, the Orioles gave Alonso a five-year contract worth $155 million, one of the largest in franchise history. At the time of the agreement, MLB emphasized that Baltimore already had several options at first base, but the club was looking for a bat capable of changing a game with a single swing. Exactly that scenario unfolded against the Mets: the team was one inning away from defeat, and Alonso brought the score back level with one swing and opened the path to victory in extra innings.
The drama continued even after the 300th home run
The 3-3 tie did not end the evening. In the 10th inning, Baltimore moved ahead again when Christian Encarnacion-Strand scored on a wild pitch by Daniel Duarte. The Mets then responded with a double by Marcus Semien and tied the game at 4-4, sending the game to the 11th inning. Then Coby Mayo, with two outs, drove a pitch from Jonathan Pintaro deep into the field and completed the trip around all the bases before the defense could finish the play. MLB officially recorded the hit as a three-run inside-the-park home run, Mayo's 24th home run of the season and the first such hit of his career. Statcast recorded an exit velocity of 106.9 mph and an estimated distance of 410 feet, about 125 meters.
Mayo thereby gave the Orioles a 7-4 lead. In the bottom half of the 11th inning, Bo Bichette cut the deficit to 7-5 with an RBI single, but New York was unable to extend the game further. Kittredge induced Carson Benge to fly out for the final out and recorded his 10th save of the season. MLB's official game summary states that Baltimore finished with eight hits and seven runs, while the Mets had 12 hits and five runs. Alex Hoppe earned the win, Jonathan Pintaro took the loss, and the result kept alive the Orioles' hopes of catching the final American League Wild Card position.
For Alonso, the way the game unfolded further increased the significance of his 300th home run. Had the hit come with a large score difference or in a game without competitive importance, the evening probably would have remained primarily a personal milestone. Instead, the hit tied the score in the final regulation inning and enabled Baltimore to reach victory only after two more innings. That is why, even among his teammates, the emphasis after the game was on the timing of the big hit, not merely on the round number in Alonso's statistics.
Milestone ball ended up back with Alonso
The story did not end with the final out. According to a subsequent MLB report, the ball from Alonso's 300th home run was caught by a group of Mets fans, and they returned it to the player after the game. Alonso met them outside the visiting clubhouse, thanked them and in return signed the items they had brought. MLB states that two of the three fans were wearing his Mets jerseys, and Alonso personalized the autographs with a message noting that the jerseys had been present at the game in which he hit his 300th home run.
He then brought them three new baseball bats, which he also signed, and offered the visitors the opportunity to attend an Orioles game at Oriole Park at Camden Yards with tickets and access to batting practice. That meeting further underscored how different Alonso's return to Queens was from the typical story of a star returning to play against his former club. There was not only an official welcome video and applause before the game; the support continued even at the moment when his hit directly harmed the home team's result. In professional sports, especially during the closing stretch of a season, such a relationship between the stands and an opposing player is rarely seen in such a clear form.
For Mets fans, that home run was simultaneously a reminder of seven seasons in which Alonso became the face of the club's power hitting. For Baltimore, it was evidence of why the club invested in him with a long-term contract and why it wants him in the middle of the lineup during the final stretch of the season. And for Alonso himself, the number 300 arrived at the stadium where he had hit most of his most important home runs, but for the first time in the colors of another team. According to MLB, it was his 124th home run at Citi Field and the first among them that he did not hit as a Mets player. It was precisely that paradox - the former franchise record holder tying the game against the Mets and then receiving an ovation from the home crowd - that transformed an ordinary statistical milestone into one of the most memorable scenes of the closing stretch of the 2026 MLB season.
Sources:
- Major League Baseball - report on Pete Alonso's 300th home run, the crowd's reaction, the historical context and the Orioles' position in the Wild Card race (link)
- Major League Baseball - official video and Statcast data for Alonso's 300th home run against Kodai Senga (link)
- Major League Baseball - official play-by-play and key actions from the Baltimore Orioles - New York Mets 7-5 game on September 15, 2026 (link)
- Major League Baseball - data on Coby Mayo's inside-the-park home run in the 11th inning (link)
- Major League Baseball - report on Alonso's first return to Citi Field as an Orioles player (link)
- Major League Baseball - overview of Alonso breaking the Mets' home run record in 2025 (link)
- Major League Baseball - official all-time New York Mets home run statistics (link)
- Major League Baseball - data on Alonso's 2019 rookie season and his record of 53 home runs (link)
- Major League Baseball - official announcement of the 2019 National League Rookie of the Year Award (link)
- Major League Baseball - report on Alonso's five-year, $155 million contract with the Baltimore Orioles (link)
- Major League Baseball - report on the milestone ball being returned to Alonso and his meeting with Mets fans after the game (link)