The Cubs want to keep riding the hot hand as they look to trot out their best lineup.

That means bringing back one of their best offensive hitters in a not-so-new position and optioning one of their top prospects to the minor leagues.

Thursday afternoon, the Cubs activated Cody Bellinger from the injured list and optioned first baseman Matt Mervis to Triple-A Iowa.

Bellinger was in the Cubs lineup on Thursday at first base as the Cubs look to ease his return from a bone bruise in his left knee he suffered while making a catch against the wall in Houston. He’ll continue at first base as he continues to “build back up for [center field].”

He delivered a go-ahead double in the 5^th inning for the Cubs — a single that he stretched with his hustle into a double.

The 27-year-old was a key cog for the Cubs offensively before his injury — he was hitting .271/.337/.493, a 122 weighted runs created plus, 7 home runs and 20 RBI. The Cubs struggled offensively in his absence — his left-handed bat lengthened the Cubs’ lineup and gave opposing pitchers another look.

Here’s how the Cubs performed offensively before and during Bellinger’s injury:

It’s a bit unrealistic to assume that the Cubs’ offense will look like they did in April immediately with his return — he has missed nearly a month of games — but the Cubs know what he can do.

In his absence, Mike Tauchman has filled in strongly at center field, hitting .299/.415/.343/120 wRC+. That allowed the Cubs to move Bellinger to first base, a position he’s played in 262 games in his career in. First base this season has been a weak spot for the Cubs — they’re last in wRC+ from the position (67), 27^th in average (.219), 29^th in slugging (.327) and last in fWAR (-1.8). Essentially, the Cubs are hoping that his production can provide a boost while Tauchman continues to play strongly in center.

By doing that, that allows Mervis to go down to Iowa and try and recapture some of the form he had before he was called up to the majors in May. Mervis was hitting .286/.402/.560/135 wRC+ with 6 home runs and had 36 home runs in the minors last season across three levels. But he struggled in his first taste of major league baseball, hitting .167 with 3 home runs and a 47 wRC+.

“Just getting a little bit of a reset for him in a moment where Belli will hold down first base for a little bit,” manager David Ross said. “I’m sure he’ll be back as soon as he feels like he’s ready and just gets some confidence back in there.”

For Mervis, part of that reset is adjusting to the mental aspect of the major leagues. Ross called him “an intense young man” and dealing with failures that are common to young players in their first taste of the big leagues was a learning curve for Mervis.

“If I look back on some of the young guys that we had, it’s rare that guys don’t come up and struggle,” Ross said.

Ross and president of baseball operations Jed Hoyer stressed the importance of not taking every out or shortcoming so hard.

“This is a really hard game,” Ross said. “You gotta continue to find the positives within the at-bat right now. I think Jed mentioned some of that in our meeting yesterday with Mervis. It’s just like sometimes you gotta find the positive and the negative just so you can keep yourself sane in this game.”

That’s one area Mervis will continue to grow in — one that can only be learned through experience. Almost every major leaguer has gone through it. Current Cubs Ian Happ and Nico Hoerner have been optioned to the minor leagues as top prospects and returned to carve out successful big-league careers. Bellinger was an MVP and struggled in 2021 and 2022 before rediscovering his form in Chicago.

“I think the hardest thing to do in sports is to hit a baseball consistently,” Bellinger said. “He definitely wanted more results on the field offensively, but I was proud of him for what he did defensively. I thought he looked really good at first base.

“The talent’s there. He’ll be just fine.”