CHICAGO -- The possibility of Yu Darvish returning from the 10-day disabled list in mid-June became less likely on Sunday when Cubs manager Joe Maddon said he is unsure whether the right-hander will pitch before the All-Star break.

"I think we'll know more by the end of this coming week exactly what we think about hopefully being able to lay out a plan about getting him back," Maddon said before Sunday's finale vs. the Pirates. "But we're not at that point yet."

Darvish played catch four of the last five days, and Maddon said he will throw again on Monday in Chicago while the Cubs travel to Milwaukee for a three-game series against the Brewers.

There has been no specific timetable for Darvish's return since he was placed on the DL on May 26, retroactive to May 23, though it was a good sign when an MRI a few days later revealed no structural damage to the 31-year-old's right arm. Instead, the Cubs said the MRI showed right triceps inflammation.

This is the second time Darvish has been on the DL this season after signing with the Cubs in February for $126 million over six years. This one, being an arm injury, is more of a concern than when he missed time with the flu earlier in May.

Darvish has had arm injuries in the past; he underwent Tommy John surgery in May 2015. The potential severity of arm injuries on top of what Maddon called the "nature of the times" could be the reason for all the uncertainty.

"I think we tend to be a little bit more on the conservative side -- everybody does, not just us," Maddon said. "Everything is so scrutinized. If in fact you permit somebody to come back too quickly and then all of a sudden [he gets hurt again], you're going to get heavily criticized for it."

Battle with the Brewers

The Cubs open up a three-game series vs. the Brewers on Monday at Miller Park with the two clubs fighting for the top spot in the National League Central.

It's only the middle of June, but every series between the two teams matters in what figures to be a tight race down the stretch.

Maddon said he wants his club to stay grounded through it all and not get too caught up in the implications of a few midseason games.

"The best way to approach when you're playing against really good teams within your division is to not get too farsighted," Maddon said. "Always the trap is to get caught in the macro-moment. Don't do it, just don't do it."

Matthew Martell is a reporter for MLB.com based in Chicago.