But that ended with Lucas Duda's sharp line drive up the middle that Marmol snared, leaving Ike Davis in no-man's land between first and second base for an easy double play.
"It was just some bad baserunning by me," said Davis, who drove in two of the Mets' ninth-inning runs as a pinch-hitter with a line-drive single past the outstretched glove of second baseman Darwin Barney.
Jordany Valdespin drove in the other run in the ninth with a homer into the Mets' bullpen, which saw plenty of action after Santana's early exit.
The left-hander struggled from the outset, surrendering a home run to Reed Johnson on the second pitch of his 4 2/3-inning outing. It was an ugly blip on the first-half radar, maybe the worst of Santana's 17 starts in a season that began with concern about whether he would even be ready for Opening Day and included him throwing the franchise's first no-hitter.
The Cubs' 13 hits were the most Santana allowed in a single game, tying the 13 St. Louis managed against him in 2010, before his shoulder gave out.
"Coming into this season, it was such a big question mark," Wright said. "He answered that question. He'll be ready for the second half."
Arizona had a previous season-high nine hits against Santana on May 5, but he scattered them across seven innings and held the D-Backs to three runs in a win. But three of the 13 Cubs hits cleared the fence, and Chicago strung the rest together, mostly in a five-run fifth inning that ended Santana's day.
It began again with Johnson, who started the fifth with an infield single and stepped on Santana's right ankle in the race to the bag. Santana felt it on the mound, he said, but it had nothing to do with him allowing hits to six of the next seven batters.
That, he said, was simply poor control.
"You noticed it early in the game," said manager Terry Collins. "You don't see him spiking that many fastballs early in the game. As he warmed up, [pitching coach Dan Warthen] said he looked great. It was just one of those nights."
Johnson raised his career average against Santana to .516 (16-for-31), while 22-year-old rookie Anthony Rizzo went 4-for-5 and belted a three-run shot into the Mets' bullpen in his first game against the two-time Cy Young Award winner.
"I was very excited to face him -- a Cy Young winner, threw a no-hitter a couple weeks ago," Rizzo said. "I just tried not to do too much against him."
He did not need to. The Cubs received production throughout their lineup, following Rizzo's homer with another two batters later from Jeff Baker. The next three batters singled, ending Santana's night after 89 pitches.
This is what it could have been like every night for Santana. Prior to the game, Collins repeated -- as he has every time he is asked just how good he thought Santana could be in his first season back from shoulder surgery -- he had no idea what to expect from the left-hander. He just never thought it would be this good.
"[Santana's] human, so he's going to have a bad start every now and then," Wright said. "We kind of stole one yesterday, and today we just ran out of gas there late."