Even though his concerns remain, the pitcher intends to play this season, largely because of his teammates' conviction.
"It was a tough decision but everyone is doing it (playing)," Darvish said Sunday, according to ESPN's Jesse Rogers. "Everyone has concerns but everyone decided to play so it makes it easier of me to make a decision to play.
"I still have concerns."
Darvish was admitted to an Arizona hospital in March after experiencing flu-like symptoms, and at the time he was worried his sickness could have been the coronavirus.
The Japanese hurler didn't end up contracting COVID-19, and he's in summer camp with the Cubs. No Chicago player has tested positive for the virus.
"I came here making sure everyone is doing the right thing, and then I had it in mind, if they're not, I was ready to go home," Darvish said.
The 33-year-old is one of the Cubs' top options to be the Opening Day starter after posting tremendous second-half numbers in 2019, including a 2.76 ERA with just seven walks in 13 starts.