CHICAGO -- Cubs manager David Ross said on Saturday that left-hander José Quintana is ready to rejoin the team's pitching staff. Now Chicago just has to determine the best way to utilize the veteran lefty.

"We're still kind of internally talking about those things," Ross said prior to Saturday's game against the White Sox. "There's kind of a lot of factors."

Those factors involve both the rotation and bullpen.

First, the Cubs will need a fifth starter on Tuesday in Detroit. Quintana (10-day injured list, left thumb) could be activated for that outing, but Chicago might also have right-hander Tyler Chatwood available again. Chatwood (10-day IL, back) threw a bullpen session on Saturday and will be eligible for activation by Tuesday, too.

Ross also mentioned right-handers Colin Rea and Adbert Alzolay as possibilities for the start on Tuesday. Rea is currently in Chicago's bullpen. Alzolay (MLB Pipeline's No. 7 Cubs prospect) came up from the alternate training site in South Bend, Ind., for Wednesday's doubleheader against the Cardinals and logged five impressive innings.

"It's a guy that's going to pitch big innings for us this season," Ross said of Alzolay on Wednesday. "He's a huge depth piece that we have, and you [saw Wednesday] what he's capable of. I was extremely pleased."

Another factor is the Cubs' need for another lefty relief option. Kyle Ryan is currently the only left-hander in the bullpen, which has been without Brad Wieck (45-day IL, left knee) for most of the season. Entering Saturday, Chicago had allowed a .294/.428/1.059 opponents slash line in left-on-left relief situations this year.

Quintana's most recent simulated game was a 28-pitch, two-inning showing on Friday in which the Cubs "let him kind of air it out" to see what that looked like, per Ross. The manager confirmed that Quintana, who has started 246 of his 250 career MLB games, is a bullpen possibility.

"Definitely," Ross said, "we've had conversations with Q on how we want to build him back into the team. And that is an option, yes."

In a discussion with reporters on Friday, Cubs president of baseball operations Theo Epstein raved about the recent improvement by the team's bullpen as a unit. That said, Epstein noted that targeting help for facing lefties is on Chicago's list for the Aug. 31 Trade Deadline.

"One thing we'd like to do," Epstein said, "with Brad Wieck being hurt almost the entire year and Kyle Ryan being the only lefty, [is see] if we can get some help. It doesn't have to necessarily be a left-handed reliever, but somebody who can get lefties out. That would help us, help stabilize the 'pen some more."