CHICAGO -- Coming out of Spring Training, the decision to use Wei-Yin Chen as a reliever was a relatively easy one. The Marlins committed to their young starting candidates, which solidified a spot for the veteran left-hander in the bullpen.

Figuring out his role wasn’t the issue. Adjusting to it is a different story. As a long reliever, Chen never knows when he will be used. If the starters work deep into games, he can go long stretches without seeing action.

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On Thursday afternoon, after Trevor Richards was tagged for four runs in five innings, Chen got the call for the first time in six days, and he tossed two scoreless innings in the Marlins’ 4-1 loss to the Cubs in the series finale at Wrigley Field.

Chen has now gone four straight appearances (six innings) without allowing a run. It’s a big improvement since he was tagged for 10 runs in two innings on April 9 at the Reds. Since that miserable night at Cincinnati, Chen has given up three runs in nine innings over his last six outings.

“He's showing up and he's making himself valuable to us, from the standpoint of using him in different areas,” Marlins manager Don Mattingly said.

In the grand scheme of things during a rebuilding year, throwing two scoreless at Wrigley Field on a day Miami dropped its third straight, and lost the series, 3-1, may not seem like much. But for a young pitching staff, these are valuable innings, because they save the rest of the bullpen and Chen shows he has value on a team in a new role.

It's a type of performance that doesn't go unnoticed, and Mattingly hinted it may lead to more work.

“The more outs you get, it seems like the more likely you are to give the guy the ball,” Mattingly said.

Thus far, Chen has been used primarily for multiple-inning opportunities. It's possible he could also be called upon more situationally, against tough lefty hitters.

Chen’s ERA was 24.75 on April 9. But after his two innings on Thursday, it’s down to 9.69.

“I try not to worry about all those stats,” Chen said through his interpreter. “Now, when I get on the mound, I try to find a comfortable way to pitch. At the early part of the season, I was worried about all kinds of stuff in my head. Now, I just want to keep things simple.”

The Marlins grinded out at-bats off Yu Darvish, who lasted four innings and threw 97 pitches. Darvish walked six and struck out seven. Rosell Herrera's RBI single in the fourth inning made it 2-1, but that was as close as they would get.

Richards is one of Miami’s better young starters. On Thursday, he was victimized by two home runs -- the first a solo shot to Kris Bryant in a two-run first inning. And in the fifth inning, Anthony Rizzo went outside the zone, scraping a curveball from one knee and driving it for a two-run homer, giving the Cubs a three-run cushion.

Rizzo’s homer turned into the big blast of the day. The fact that he was able to connect stunned even Richards, because the pitch was down and far out of the strike zone.

“It was pretty much where I wanted to pitch it,” Richards said. “If he swung at it, I thought he wouldn't make good contact. If he didn't swing at it, that's OK, I'd go back to something else. He went down and got it, and put it out.”

Since he was rocked in Cincinnati, Chen also has scrapped his slider and is mixing in a cut fastball as well. Of the 32 pitches he threw on Thursday, 10 were cutters, although the pitch is still being read as a slider by Statcast.

“This year, I'm throwing the cutter instead of the slider,” Chen said. “In the past, I'd tried to be too fine with the slider, but it wasn't there this year. So I'm throwing the cutter instead. I've been using it more and more.”