Santana cruised from there into the seventh, when Molina hit a one-out drive to deep left. Baxter, who grew up rooting for the Mets only 10 minutes from where Citi Field stands, raced back and made a terrific catch before crashing full force into the fence.
Baxter stayed down on the warning track as Mets trainers, players and coaches rushed out to him. Santana crouched in the infield with a couple of teammates and then made a few warmup tosses to stay loose.
"When I saw him running back onto the warning track and he made that play, it was amazing. An outstanding play and he saved the game," said Santana, traded to the Mets by Minnesota before the 2008 season. "All these guys, I want to thank them for what we accomplished."
Baxter walked off the field under his own power, with trainer Ray Ramirez holding the outfielder's left arm because Baxter had no feeling in it. The Mets said Baxter has a bruised left shoulder and was having more tests.
"I'm glad I had a chance to be part of it. It's a great night for the Mets," Baxter said.
Lucas Duda hit a three-run homer off Adam Wainwright (4-6) and drove in four runs, tying a career high. Daniel Murphy added three RBIs.
The San Diego Padres, who started play in 1969, are now the only team without a no-hitter.
The Mets' seemingly endless pursuit had become something of a famous quest, with at least one website dedicated to counting off their total number of games without a no-hitter each day during the season. Radio announcer Howie Rose often did the same when the opposing team got its first hit.
The list of pitchers who have thrown no-hitters after leaving the Mets includes Ryan and Seaver, both Hall of Famers, plus Gooden, David Cone, Mike Scott, Hideo Nomo and Humber.
Ryan, in fact, pitched a record seven no-hitters. Now the president of the AL champion Texas Rangers, he's still aware of the Mets' no-hit history - or lack thereof.
"To me, it was phenomenal," he said through a team spokesman on the 37th anniversary of a no-hitter he threw for the Angels. "If you look at the history of their organization and the type of pitching they had at times, plus the fact they had pitchers throw no-hitters with other clubs."
Seaver came within two outs of a perfect game in 1969 and fell one out shy of a no-hitter in 1975, the previous time a Mets pitcher had made it into the ninth without yielding a hit.
Notes: Santana's previous career high was 125 pitches. ... It was the eighth no-hitter pitched against St. Louis and the first since Fernando Valenzuela for the Los Angeles on June 29, 1990. ... Mets 3B David Wright said in a radio interview on WFAN that he won't talk to the team about a new contract until after the season because he doesn't want his situation to be a distraction for the team. Wright's salary is $15 million this season and New York holds a $16 million option for 2013, which gets voided if he is traded. After that, he can become a free agent. ... Replays showed Cardinals pinch-hitter Shane Robinson was hit on the hand by a pitch in the eighth. He started toward first, but Cederstrom called it a ball.
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