PHILADELPHIA -- After making his Major League debut against the Pirates last Monday, Cardinals left-hander Drew Rom was the first to say there was a lot of anxiety -- and it showed on the mound, as he allowed eight runs (six earned) in just 3 2/3 innings.

It looked like he might have been on his way to a similar outing on Sunday afternoon, but he settled down and pitched well in a 3-0 loss to the Phillies at Citizens Bank Park. Rom struck out six batters while allowing just two runs off five hits and one walk over 5 1/3 innings.

In this game, Rom had his mechanics in order, didn’t have to rush to throw his pitches and -- the biggest thing -- his anxiety was gone.

"I was like, 'We are going to take it pitch by pitch. I can breathe and relax. I have time,'" Rom said.

Rom was able to relax on Sunday after talking to teammates such as Adam Wainwright and former Orioles teammates DL Hall, Spenser Watkins and Nick Vespi.

"Waino has been a veteran presence. He helps me understand the game a lot more," Rom said. "He helps me understand how to be a big leaguer -- how to go out and do your thing, trying to mature as a player and handle your stuff."

Wainwright said Rom stayed within himself and didn’t try to do extra during Sunday’s game.

"What gets you to the big leagues is all you need to do," Wainwright said. "So many times, young guys come up and they think they need to do something better or something different when they get here. Until a hitter tells you to, that is never the right thing to do. Be yourself until the hitter tells you to change yourself."

The way the game started, Rom had to wonder if he was in for another long day. Kyle Schwarber teed off on Rom's first pitch for a Statcast-projected 436-foot home run over the center-field fence to give Philadelphia a 1-0 lead.

Though he had obviously never faced the Phillies prior to Sunday, Rom faced Schwarber in live batting practice during the offseason in Cincinnati. Schwarber ended up going 1-for-3 against the left-hander in Sunday’s game.   

"It was time to take a breather [after the homer] and just figure it out pitch by pitch at that point," Rom said. "Knowing Schwarber, I’m probably going to hear from him during the offseason a little bit. It will be entertaining to hear from him. But I did get him [with a strikeout]."

After walking Bryce Harper to put runners on first and second, Rom retired nine of the next 11 hitters he faced. It helped that his sweeper was effective.

"It was a lot more of, 'Let me pitch rather than just try to force everything, … try to place everything super perfect or super fine,'" Rom said of his approach. "It’s a matter of letting myself calm down and work."

Before leaving the game with one out in the sixth inning, Rom had allowed his second run of the game an inning earlier. Left fielder Alec Burleson was unable to catch a deep fly ball near the wall off the bat of Johan Rojas, who later scored on a sacrifice fly by Trea Turner.

"Rom threw a lot more strikes. When you look at his usage, he mixed a lot better, kept guys more off-balance than his first outing," Cardinals manager Oliver Marmol said. "It was good for him to walk off the mound feeling good about it."