Undrafted rookies John Timu and Harold Jones-Quartey spent most of the season watching the Bears defense from the sideline. But that only fueled their determination.

Not satisfied to just earn an NFL paycheck, both players remained fully invested in practice and meetings and have made the most of their chances to play late in the season.

John Timu celebrates with coach John Fox after recovering a fumble against the Bucs.

"They're examples of guys who've stayed into it mentally even when they weren't playing, so when they did get their next opportunity, they were ready to go from a mental standpoint," said defensive coordinator Vic Fangio. "They didn't take the attitude, 'Well, I'm not playing' and then slack off mentally as far as knowing the defense."

A three-time captain at Washington, Timu played in the Bears' first four games this season on special teams. He then spent 10 weeks on the practice squad before being promoted to the active roster Dec. 15 and supplanting Christian Jones in the starting lineup.

Timu led the Bears with nine tackles and helped limit Adrian Peterson to 63 yards in a loss to the Vikings Dec. 20 and then became the first Bears rookie since Bryan Knight in 2002 to recover two fumbles in a game in last Sunday's win over the Buccaneers.

Jones-Quartey replaced the injured Antrel Rolle at safety Oct. 4 against the Raiders and then started the next two games in Kansas City and Detroit. But the University of Findlay product lost his job with the No. 1 defense and had to wait nine weeks to get it back.

"He steadily showed progress in practice, both in the reps with the defense and on the scout team," Fangio said, "so we thought it was warranted to give him another shot back there."

Jones-Quartey made the most of his second chance, generating two takeaways with a forced fumble and an interception last Sunday in Tampa. The pick came near the goal line on a jump ball pass from Jameis Winston to running back Charles Sims.

"I love the energy that Harold brought and that he brings every day in practice," said outside linebacker Sam Acho. "You watch this guy practice and he's flying around every single play, flying to the ball, picking the ball off, forcing fumbles, and he does it in the game."

Jones-Quartey entered the NFL this year as an undrafted free agent with the Cardinals. He was later claimed off waivers by the Bears following final cuts. Coach John Fox said Friday that Jones-Quartey possesses the "football character you want in your organization."

"He's got good speed," Fox said. "He enjoys contact. He plays the game, I call it, with your hair on fire. He plays it hard and crisp, and now it's just a matter of learning the game a little bit better. He was a small school guy, hadn't played football his entire life. But he has the components that we're looking for and I'm pleased we got him."