CHICAGO -- Lefty Brailyn Marquez has never thrown a pitch above Class A, but his name is on the mind of plenty of Cubs fans as October looms. That is understandable, given that Chicago's top prospect wields a fastball that hits triple digits.

Marquez's development has continued this season at the Cubs' alternate training site in South Bend, Ind., giving him a chance to test his arsenal against some hitters with MLB experience. General manager Jed Hoyer was asked Sunday whether Marquez might still reach the Majors this year.

"He's throwing really well in South Bend," Hoyer said. "I don't want to comment sort of beyond that, other than the fact that he's worked really hard with our guys at the alt site. I think he's progressed nicely. I think he's gotten better and better kind of by the week being there."

MLB Pipeline currently ranks the 21-year-old Marquez as the Cubs' No. 1 prospect and No. 64 in the Top 100 overall.

Last season, the lefty had a 3.13 ERA with 128 strikeouts and 50 walks in 103 2/3 innings (22 games) between Class A South Bend and Class A Advanced Myrtle Beach. Over his final 12 outings, Marquez piled up 76 strikeouts against 23 walks with a 2.01 ERA across 62 2/3 innings.

"I think people forget that this is a guy that has never pitched above high-A ball," Hoyer reminded. "He's made nice progress this year and is certainly someone we have a lot of high hopes for going forward. We'll have to make a decision on him, as far as whether he's in that 40-man [playoff] roster or not."

Worth noting
• Hoyer echoed manager David Ross' evaluation, noting that left-hander José Quintana (10-day injured list, left lat) "looked sharp" during Saturday's sim game. The GM said the plan remains to activate Quintana during the upcoming series in Pittsburgh.

"Which day? I don't know yet. We're still determining that," Hoyer said. "But I think he's trending towards the Pirates series."

Quintana could join the Cubs' bullpen, but it is also worth noting that Chicago has yet to announce a starting pitcher for Tuesday's game in Pittsburgh.

• Hoyer said the Cubs are not currently looking into "surgical intervention" for righty Tyler Chatwood (10-day IL), who has had a series of setbacks with his right elbow and forearm injuries. The GM noted that Chatwood played catch up to a distance of 105 feet on Saturday.

"He's still hopeful that, if we play for a while, that he'll be able to help us," Hoyer said.

• Prior to Sunday's game, the Cubs recalled designated hitter José Martínez from South Bend and optioned lefty reliever Josh Osich to the alternate training site. Martínez was acquired via trade from the Rays on Aug. 31, but went 0-for-14 for the Cubs before being optioned on Sept. 8.

Quotable
"It's been an incredible contract, and he's been such an amazing contributor for us and leader, teammate. He's been fantastic. This is exactly what we wanted when we signed him. He's given us everything we hoped for. I wasn't thinking that [Wednesday could've been his last start at Wrigley Field]. I look forward to him making a lot more starts and throwing a lot more big pitches for us. And then we'll talk about next season when it's appropriate." -- Hoyer, on Jon Lester's impact and future with the Cubs