LAKE FOREST, Ill. -- Chicago Bears starting quarterback Mike Glennon had nothing but positive stuff to say about understudy Mitchell Trubisky, who's been running the second team since Mark Sanchez suffered a knee injury during OTAs.

"Yeah, he's been great," Glennon said. "He works really hard at it. He asks questions. He's done a really good job of learning the offense, understanding what we're trying to accomplish, and I think he does a great job picking that up for being a rookie."

Only time will tell if Trubisky takes any meaningful snaps in the regular season. For now, Glennon -- scheduled to earn $16 million guaranteed in 2017 -- is secure in the No. 1 spot.