Rookie cornerback Chris Greenwood, shown during minicamp in May, made his practice debut for Detroit on Wednesday. (US Presswire)

For most of Detroit’s players, Wednesday’s workout was simply an extra chance to prepare for Monday’s key divisional matchup with Chicago.

For rookie CB Chris Greenwood, it was a key step toward realizing his dream of being an NFL player.

Greenwood practiced for the first time all season after his PUP waiting period expired Tuesday, and he appeared to complete the drill portion of practice that was open to media without incident.

“It felt good to finally get out there and play football again,” he said.

Detroit’s decision to select Greenwood in the fifth round of the 2012 draft surprised many experts. He was a virtual unknown heading into the draft. He played college football at Albion College (Mich.), a small NCAA Division III school in the south-central part of the state. Lions’ management touted Greenwood’s athletic ability and speed as the principal reasons for selecting him over several athletes from more well-known Division I schools.

Greenwood’s performance during non-contact offseason drills appeared to justify the decision to select him, but a surgery to correct a sports hernia led to him being placed on PUP before training camp.

One of the major questions surrounding Greenwood following the draft was whether he would be able to adjust to the speed and complexity of the NFL after playing small-college football. Greenwood says the time spent studying Detroit’s playbook while he was on PUP has helped his development.

The next step, he says, is getting accustomed to contact activities. He acknowledged he has work to do before he’s ready for game action but says he’s ready for the challenge.

“I feel a little bit (behind),” he said. “Not too much, though. I’ve been taking mental reps, so I’m OK.”

Greenwood’s return to the field couldn’t come at a better time for Detroit’s injury-depleted secondary. Cornerbacks Bill Bentley [shoulder] and Jacob Lacey [concussion] missed Wednesday’s workout, giving Greenwood the opportunity to take extra reps in drills. Coach Jim Schwartz wouldn’t comment on whether Greenwood would be elevated to the Lions’ active roster before Monday’s game -- the team has 21 days to evaluate his fitness before removing him from PUP status -- but he did say that Detroit’s coaches were focused on preparing him for game action.

“We’ll get [Greenwood] up to speed as quickly as we can,” he said.

Lions address DB depth issues by working out two familiar faces: With Bentley and Lacey’s status for Monday’s game uncertain, the Lions are left with just two healthy cornerbacks on the active roster. Detroit took a step toward addressing that lack of depth Wednesday by working out Alphonso Smith and Justin Miller. Both players spent training camp with Detroit before being released on roster deadline day. The pair left the Lions’ Allen Park, Mich. practice facility without signing contracts. Smith, who spent two seasons with the Lions, told that the process of working out for his former team was “very odd,” and “borderline uncomfortable.” But he said he would love to have another stint with the organization.

Burleson gets rest day, three others miss drills: In addition to Bentley and Lacey, four other players missed Wednesday’s open portion of practice. DT Corey Williams (knee) remains week-to-week while he recovers from surgery. LB DeAndre Levy (undisclosed), DE Cliff Avril (leg) and WR Nate Burleson were also held out of the workout. Burleson said his absence was simply scheduled rest, and it’s likely that the same was true for Levy and Avril. Detroit isn’t required to release a practice report until Thursday, however, and team officials didn’t clarify the official reasons behind the players’ absences.

Follow Lions reporter John Kreger on Twitter at @CBSLions and @JohnKreger.