Hoping for thumbs up

FOXBOROUGH - The widely held assumption is that the replacements for cornerbacks Asante Samuel and Randall Gay will come from among the five newcomers on the Patriots' roster - veterans Fernando Bryant, Jason Webster, and Lewis Sanders, and rookies Terrence Wheatley and Jonathan Wilhite.

But an answer could be a player who was already on the roster, second-year cornerback Mike Richardson.

Richardson, a 2007 sixth-round pick out of Notre Dame, was one of the pleasant surprises of training camp last year and appeared on track to make the team before he broke his left thumb in the third exhibition game, against Carolina.

He was placed on injured reserve, but yesterday the 5-foot-11-inch, 190-pounder was back on the field for passing camp, eager to compete in the Patriots' cornerback derby.

"You never know when you're going to lose somebody, and there is always going to be somebody ready to step in," Richardson said. "It's up to us to be prepared and be ready to step up and make the plays."

Richardson, 24, acknowledged the thumb injury was "definitely a blow."

"I just had to take it in stride," he said. "I just had to work on getting better rehabbing and come back out here and try to make a name for myself."

Richardson's rookie season was not a total loss. He was able to work on the mental part of playing cornerback, picking up on reading offenses and knowing what receivers want to do in certain situations and formations.

Richardson said passing camp sessions such as yesterday's, which featured few veterans and was mostly geared to the younger players, are beneficial.

"It helps out a lot, especially for a guy like me that wasn't out here practicing at all really last year," said Richardson. "It helps me get back in the swing of things."

The way Richardson sees it, somebody has to replace Samuel and Gay, both of whom departed via free agency, and he knows the Patriots make decisions on playing time based on performance, not pedigree. Both Samuel, a fourth-round pick, and Gay, an undrafted free agent, are proof of that.

"It's all about what you do and what you show them out on the field, practicing," said Richardson. "It's anybody's job. Anybody that shows up day in and day out and does the right things, they're going to progress."

Christopher L. Gasper can be reached at cgasper@globe.com.