CHICAGO -- Everything had seemingly been going very well for Cubs starter Yu Darvish since the All-Star break, but things took an unexpected turn on Sunday as the Cubs announced Darvish would miss his scheduled start against the Brewers with right forearm tightness.

Tyler Chatwood made the spot start in Darvish’s place, allowing one run off three hits over 3 2/3 innings with seven strikeouts and four walks.

Darvish has been experiencing the forearm tightness in his past five starts, according to team officials. He's been able to manage it and continue to pitch well despite the discomfort.

The arrival of expanded rosters on Sunday offered the Cubs an opportunity to give Darvish a few extra days of rest.

“I really believe he’s going to make his next start,” Cubs manager Joe Maddon said. “We just wanted to back off right here with that little bit of a concern, and then he should be back.”

Darvish’s return to dominance has seen one of the best pitchers in the National League going 3-2 with a 2.93 ERA in nine post-All-Star break starts. He had 72 strikeouts and just three walks in 55 1/3 innings pitched over that span.

While the Cubs have downplayed the severity of Darvish’s latest ailment, there is some possible concern as right forearm tightness is often a precursor for Tommy John surgery. Darvish underwent Tommy John surgery in 2014 as a member of the Texas Rangers.

“It’s been varying levels. It’s been some starts where it was bugging him and you’d see him on the mound trying to loosen it up and there’s other times where he’s going six innings and feeling great,” Cubs pitching coach Tommy Hottovy said. “When you have that forearm stiffness the day before your start, it’s a little scarier for us. Just make sure he’s taken care of and have him ready for his next start.”

The 33-year-old right-hander also missed most of the 2018 season dealing with right triceps tendinitis, pitching just 40 innings in his first season in Chicago. Darvish’s next start would most likely be against the Brewers on Saturday at Miller Park.

“Guys deal [with] stuff throughout the course of the year but for guys there are varying levels of how it affects them pitching-wise,” Hottovy said. “But any time it’s a day before your start and you’re doing all you can to make [that start], we don’t want a guy going out there trying to survive.

“We want Darvish to be the best version of himself and that he comes through this for the stretch run is important. It’s just one of those things that we need to take care of right now as opposed to trying to push him through it and cost him even more time.”