Thompson and Wellemeyer are in competition for a starting spot in the Cardinals' rotation, and Thompson entered Saturday's game against the Marlins with two runners on base -- both of them Wellemeyer's responsibility. A base hit off the bat of Mike Jacobs would have cost Wellemeyer at least one run.
This is no cutthroat competition, though. Besides, Thompson's manager and pitching coach are no fools -- they're not just looking at spring ERAs as they make their decisions.
"Welly and [Anthony] Reyes are two of my best friends on this team," Thompson said. "So I would never be out there hoping they have a bad outing so I can have a good one. Welly did a great job today, and I got to come in behind him."
Both Wellemeyer and Thompson did more to confirm previous impressions about them than to create any new ones. Wellemeyer showed excellent stuff and occasionally iffy command, running up a high pitch count (49 in 2 2/3 innings) but not allowing any runs. Thompson pounded his sinker down in the strike zone and kept up his history as an excellent Spring Training pitcher.
The two are competing with Reyes for the final two spots in the St. Louis rotation. Reyes would seem to have a leg up for one spot, meaning it may be a head-to-head competition for one job between two friends.
"I hope the best for [Thompson]," Wellemeyer said. "He hopes the best for me. I guarantee it."
Wellemeyer allowed a single in the first inning but got a pair of ground balls and escaped quickly. Then, in the top of the second, the Cardinals offense sent eight men to the plate, including three walks, as Wellemeyer cooled on the bench.
Upon returning to the mound, Wellemeyer walked his first batter before getting out of the inning with a strikeout, a grounder and a flyout. He walked two men in the third before giving way to Thompson.
"I could have gotten ahead of the guys a little bit more," Wellemeyer said. "That will be key for next time, and the rest of spring actually. Just trying to work ahead and stay ahead."
Asked to take care of Wellemeyer's business, Thompson did so, inducing a grounder to first from Jacobs. He then breezed through two more innings, allowing only one base hit and striking out three.
Thompson even tried out a new wrinkle, throwing his changeup to right-handed batters rather than saving it for lefties only.
"I'd still like to see the ball come out of my hand a little [livelier], with a little more pop behind it," Thompson said. "But results-wise, everything was good. I had a good changeup. I struck out three guys on a changeup, which I don't normally throw to righties."
The next time they pitch, in five days, the two right-handers will flip. Thompson will get his first career Spring Training start, while Wellemeyer will come out of the bullpen. Thompson is looking forward to the chance. He's been considered part of a starting competition before, but never actually gotten the chance to start in spring.
Matthew Leach is a reporter for MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.