CHICAGO -- Cubs right-hander Kyle Hendricks will make his scheduled start against the Miami Marlins on Sunday, but the team is concerned about the veteran's start to the season.

Hendricks, 34, is 0-2 with a 12.71 ERA over four outings that includes a league-high seven home runs allowed.

"It's not one or two starts," Cubs president of baseball operations Jed Hoyer said Friday morning. "It's been four, so I think there is a level of concern, but I would also say, given his track record and given the fact that he's gotten through some struggles in the past, this isn't the first time he's struggled. No one pitches in the big leagues and doesn't have those struggles at some point."

Hendricks has always been a slow starter, but this April has been particularly bad. Opposing batters are hitting .514 off his sinker, and his four-seam fastball hasn't been much better. His changeup has also been problematic, although it was better last time out against the Arizona Diamondbacks.

Time isn't on Hendricks' side as the Cubs have a group of young pitchers pushing for more time on the mound.

"Kyle's performance needs to improve," manager Craig Counsell stated simply. "We're clear on that, and I think Kyle agrees on that."

The Cubs won't put on a timetable on needing to see improvement -- Counsell said every situation is different -- but with the return of Jameson Taillon from injury and Justin Steele not far off, the team is hoping for improvement soon.

"The velocity is the same, if not a tick up from last year," Hoyer said. "His location and execution have been poor. He's paid for it, facing good lineups."

Hendricks will get a softer landing against the Marlins on Sunday as they enter the weekend ranked 29th in OPS. That should be an easier task than the four previous opponents he faced: the Rangers, Dodgers, Padres and Diamondbacks. In between, he missed the light-hitting Rockies (in Chicago) and Mariners.

"It's been about elite, elite level of command and execution and sequencing," Hoyer said. "We haven't had that. Without those things, he's not going to get results."

Some in Hendricks' orbit want him to throw his curveball more -- he has nearly abandoned it over the past two seasons -- while others just believe it's the execution of his bread-and-butter pitches that needs to be better. Hendricks is the longest-tenured Cubs player and has survived in the majors on his sinker and changeup.

"There's a level of concern," Hoyer reiterated. "But I'm confident he'll figure it out."

With Taillon's first start of the season Friday and a doubleheader Saturday, the Cubs are hopeful for a longer stint out of Hendricks come Sunday. He has made it through five innings only once this season while the team has amassed the second-fewest innings from its starting staff overall.

"The nature of the weekend is we need innings from everybody, with what's going on," Counsell said.

The return of Taillon means Ben Brown will go back to the bullpen after a successful couple of starts, but depending on how Hendricks performs in the near future, Brown's role could change again.

Hendricks, a onetime World Series hero, is under pressure to perform in potentially his final year with the Cubs. He will be a free agent after the season.

"So much of what he does is based on execution and feel, and maybe it takes a little bit longer," Hoyer said. "His place in Cubs history is secure. I don't think anything is going to change that."