FOXBOROUGH, Mass. -- Tom Brady turned 35 on Friday, earning the Patriots' quarterback a few birthday serenades from fans at New England's training camp.

Although Brady has said in the past that he would like to play until he is 40, and has shown few signs of slowing down, the Patriots are getting ever closer to the unthinkable: life without their franchise quarterback.

After practice Sunday, Brady wouldn't put a number on how many more years he would like to play, just reiterating that he would "like to play for a long time."

Great players often combine conditioning, smarts and a love for football to remain effective into their late 30s and beyond, said Nick Caserio, the Patriots' director of player personnel.

"Joe Montana was a great player, (Dan) Marino was a great player, (John) Elway was a good player, (Troy) Aikman -- those guys were fun to watch for years," he said.

Quarterback George Blanda played until he was 48, Steve DeBerg to 44 and Brett Favre until he was 41.

Caserio cited two other examples. Vinny Testaverde was 42 when he played for the Patriots in 2006 and Doug Flutie was 43 when he played for the Pats in 2005.

Brady said after practice Sunday that he has a lot of football left in him, and that both Flutie and Testaverde were great teammates and that he learned a great deal from both.

"I'm a long ways from 42," Brady reminded reporters. "Hopefully, I'm still talking to you guys when I'm 42."

Four-year veteran Brian Hoyer and second-year pro Ryan Mallett are competing to one day replace Brady, or to be able to step in if he goes down again, as he did in 2008.