Greene has had two arthroscopic surgeries on that knee within the past year since getting hurt in the opener last season, costing him five games. He had a second procedure in May.
He went down in the second quarter of a 31-24 loss in New Orleans. Greene went to the bench, and he says he felt much better after a few minutes. The play happened so fast that Greene said he wasn't worried or scared.
''It was just a bang-bang thing,'' Greene said. ''I just kind of hit on the turf, and it got bent and I was all right.''
The Titans need Greene, who has 13 rushes for 66 yards this preseason, as they go with a committee approach at running back after cutting Chris Johnson in April. He's the veteran in the second year of a three-year contract signed in March 2013 working with Dexter McCluster and rookie Bishop Sankey.
Greene has not been wearing a brace on his right knee, and he said he doesn't like anything restricting him. He's trying to become comfortable enough running hard without thinking about his knee.
''That's the challenge thinking about it,'' Greene said. ''When you don't want to think about it, you think about it. That's the challenge, just trying to go out there and play football.''
Backup quarterback Charlie Whitehurst watched practice Monday, resting a sore finger injured when sacked in the Saints' loss. Coach Ken Whisenhunt said he doesn't anticipate Whitehurst's finger being an issue. Mettenberger finished up the game after Whitehurst was hurt and was 20 of 25 for 269 yards and two touchdowns. The rookie did fumble and was intercepted.
''It's the opportunity for Zach and Jake (Locker) to get more work,'' Whisenhunt said. ''Charlie has been doing great. We just felt like it was better to let him take the day off today.''
Notes: With the first cuts looming Aug. 26, the Titans have not made a move yet to put LB Colin McCarthy on injured reserve. He had been scheduled for a second opinion on his injured left shoulder Monday with surgery Tuesday, but he tweeted a picture of himself Friday saying surgery went great.
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