The New York Mets experienced plenty of success and charmed moments during the first five-plus weeks of the season.

But after nearly 50 years in professional baseball, Buck Showalter never expected the smooth ride to last all year.

The Mets will look to start bouncing back from their first series loss of the season Monday night, when they are scheduled to host the St. Louis Cardinals in the opener of a four-game set.

With Tylor Megill, their originally scheduled starter for Monday, heading to the injured list Sunday due to right biceps tendinitis, the Mets have yet to announce a starter, though Showalter indicated right-hander Trevor Williams (0-2, 5.73 ERA) is the likeliest choice.

Right-hander Miles Mikolas (3-1, 1.49 ERA) will start for the Cardinals.

The Mets will be continuing a seven-game homestand after a furious ninth-inning rally fell short in Sunday's 8-7 loss to the Seattle Mariners. The Cardinals concluded a six-game homestand Sunday night by cruising to a 15-6 win over the San Francisco Giants.

The Mets lost two of three to the Mariners as they dropped a series for the first time in 11 tries. New York, which won nine series and split a four-game set with the Atlanta Braves from May 2-4, was the last big league team to lose a series this season.

Even with a win Sunday, the Mets' day would have been dampened by the loss of Megill, who started a five-pitcher no-hitter against the Philadelphia Phillies on April 29 to cap a month in which he went 4-0 with a 1.93 ERA.

But Megill gave up 11 runs over 6 2/3 innings in his last two starts and reported soreness while throwing following his start against the Washington Nationals last Wednesday.

"We knew stuff like this was going to happen," Showalter said. "So it's not 'woe is me.' I don't wallow around in self-pity. We're going to look at it as an opportunity to shine."

Sights both routine and unprecedented highlighted the Cardinals' rubber game win over the Giants. The combo of starting pitcher Adam Wainwright and catcher Yadier Molina - reunited after Wainwright missed 10 days due to testing positive for COVID-19 - became the winningest battery in history by earning their 203rd victory together.

The duo previously shared the record with Warren Spahn and Del Crandall, who produced their 202 wins for the Boston and Milwaukee Braves.

And the Cardinals' easy win ended with Albert Pujols - who, like Wainwright and Molina, is expected to retire at the end of the season - making his debut as a pitcher by allowing four runs in the ninth inning. He gave up home runs to Luis Gonzalez and Joey Bart, who were five years old and four years old, respectively, when Pujols made his big league debut in 2001.

"That was fun," Wainwright said. "I just can't remember a time that ever would have happened. But that's some of the reasons why this season is magical - things like this might happen."

Williams last pitched on Wednesday, when he relieved Megill and threw 3 2/3 scoreless innings in an 8-3 loss to the Nationals. Mikolas earned the win last Wednesday, when he gave up one run over seven innings as the Cardinals beat the Baltimore Orioles, 10-1.

Williams is 4-6 with a 5.64 ERA in 19 career games (14 starts) against the Cardinals. Mikolas is 1-0 with a 1.13 ERA in three games (two starts) against the Mets.