When the Saints lined up for 11-on-11 drills on Tuesday morning, their top three cornerbacks from a year ago were not on the field.

Tracy Porter signed with the Denver Broncos in the offseason. Jabari Greer, who participated in individual drills, was held out with a sore groin. Patrick Robinson sat out with a sore shoulder he injured in Sunday’s practice.

Interim coach Joe Vitt said both players would be evaluated in the training room, adding that Robinson “could be out the next couple of days.”

Greer, Robinson and Porter accounted for 170 tackles and six of the Saints’ nine interceptions in 2011.

In their place Tuesday were Marquis Johnson, a third-year pro who did not start any games for the St. Louis Rams in 2010 and 2011, undrafted free agent rookie Laron Scott and nickelback Johnny Patrick, a third-round pick in 2011. That trio combined for 11 tackles in the NFL last year.

Still, the cornerbacks, and Johnson in particular, held their own in team drills. Johnson made two nice plays early, diving to pick off a Drew Brees pass that defensive end Cameron Jordan tipped at the line, and breaking up another Brees throw for Marques Colston.

“It’s very encouraging,” Vitt said. “There’s a long way to go, but he had a good morning.”

Hicks off PUP: The Saints cleared their top draft pick, third-round defensive tackle Akiem Hicks, off the active PUP list, but he will have to sit out three pads practices under the new collective bargaining agreement.

Hicks did agility drills on the side of the field while his teammates practiced.

Thomas returns: Tight end David Thomas, who injured his back in the first practice of training camp, returned Tuesday.

Thomas, who caught 35 passes in 2009 and 30 passes in 2010, played in only five games (with five receptions) last year and ended the season on injured reserve after suffering two concussions.

He said neither that issue nor his recent back trouble would slow him down.

“I wouldn’t be out here if I was worried about that,” he said.

Follow Saints reporter Guerry Smith on twitter @CBSSportsNFLNO.