Carlos Martinez, not Adam Wainwright, will take the mound for the Cardinals as they open a three-game set against rookie Jacob deGrom and the Mets at Busch Stadium on Monday.
The Cardinals swept the Nationals over the weekend, while New York took two of three games from the Padres.
Wainwright -- who sent the Mets home from their last postseason appearance with a curveball across Carlos Beltran's knees to end the 2006 National League Championship Series -- was scratched from Monday's start because of tendinitis. He expects to be able to make his next scheduled start, Saturday against the Phillies.
Martinez has worked out of the St. Louis bullpen all year -- he is 0-3 with a 4.67 ERA in 30 appearances -- but he has wanted to start. He'll get his chance on Monday, although he will be limited to 50-60 pitches.
"I think it's part of keeping to our word," Cardinals manager Mike Matheny said. "We've had other opportunities that didn't seem quite right, where the role he was filling in the bullpen didn't really allow this opportunity to bounce him into a start.
"We told him to keep working and he was going to get a chance. He still has a big role for us in the bullpen, but this is an opportunity that is also a necessity. We need somebody to step up and be able to take this start for Adam. We believe Carlos can do a good job of that."
deGrom has held his own in his first Major League stint -- he has a 3.44 ERA, 1.26 WHIP and 7.9 strikeouts per nine innings -- but has yet to find the win column. Early, that could be pinned on the Mets' offense, with deGrom turning in quality starts in each of his first four starts. In his last two outings, however, the right-hander has allowed a combined seven runs in 10 2/3 innings.
The most recent of those came Wednesday against Milwaukee. deGrom took the loss after getting touched up for three runs on nine hits and a walk in 5 2/3 innings.
Cardinals: Mozeliak hoping injured pitchers mend quickly
Cardinals general manager John Mozeliak said Sunday that the idea of having 13 pitchers in the long term doesn't exactly thrill him.
The Cardinals added reliever Nick Greenwood to the roster to help a bullpen that may have to log additional innings Monday with Wainwright scratched.
The decision on who might fill out the bullpen won't get any easier when Wainwright returns to the rotation Saturday, and the Cardinals may opt to return to 12 pitchers.
Tyler Lyons, who hasn't pitched since May 12 due to a left shoulder strain, made a rehab appearance at Triple-A Memphis on Saturday, lasting 2 2/3 innings while allowing one run on two hits. Mozeliak said Lyons will throw a bullpen session in St. Louis in the next few days before the team makes a decision on how to proceed.
Meanwhile, Kevin Siegrist, out since May 23 with a left forearm strain, was expected to throw a bullpen Sunday and possibly go on a rehab appearance as early as Tuesday if all goes well. The list goes on with Joe Kelly, who has been sidelined since mid-April with a left hamstring strain. Mozeliak said he could return within two or three weeks.
Mets: Bullpen put to the test
Sunday's starter, Daisuke Matsuzaka, exited after just one inning with a severe upset stomach. This put an already short-handed Mets bullpen in difficult spot.
However, the 'pen stepped up in a big way, as the Mets held on to beat the Padres, 3-1, on Sunday. Carlos Torres, Vic Black and an ailing Jenrry Mejia combined for eight-innings of one-run ball.
Mejia has been dealing with a tight back, so the Mets had already been playing with a short bullpen. The Mets might make a move to recall a fresh reliever.
Outfielder Eric Young, Jr., meanwhile, rehabbed with Double-A Binghamton over the weekend. Manager Terry Collins said after Sunday's game he expects Young to rejoin the team in St. Louis on Monday.
• The Cardinals called up Greenwood from Triple-A Memphis on Saturday. They anticipate possibly needing him on Monday against the Mets with Martinez on a pitch count.
• Mets right-hander Rafael Montero left his start with Triple-A Las Vegas over the weekend after just five pitches with what the team is calling a strained left oblique.
David Adler is an associate reporter for MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.