FOXBOROUGH, Mass. – The New England Patriots faltered badly late last season without four veteran leaders who were gone before the opener.

They faded at the end of games, gave up long plays and got thrashed in the first round of the playoffs.

So it’s a positive development that all 12 of this year’s draft picks signed before the start of training camp today. That’s 12 more youngsters for Coach Bill Belichick to look at as he tries to replace players who helped win Super Bowl championships.

The Patriots have just three players left from the team that won three titles starting in 2002: Tom Brady, Kevin Faulk and Matt Light. Only 17 remain who played in the 2008 Super Bowl, a 17-14 loss to the New York Giants.

Before last season, linebacker Tedy Bruschi and safety Rodney Harrison retired, and linebacker Mike Vrabel and defensive end Richard Seymour were traded. That left a huge leadership void that persisted throughout the season.

After the 33-14 playoff rout by the Baltimore Ravens, Belichick said, “The rookie players learn a lot every week. The second time around, hopefully, it will be an improvement for everybody.”

Rookies Julian Edelman, Patrick Chung, Darius Butler, Sebastian Vollmer and Myron Pryor all played quite a bit. Safety Brandon Meriweather, a first-round pick in 2007, had a strong season.

Linebacker Jerod Mayo, a first-rounder in 2008, played well although not as well as when he was named defensive rookie of the year.

But none of those young players has emerged as the leader the Patriots need.

In May, Brady said the Patriots lacked confidence and mental toughness. Improving that, he said then, has “been a big point of emphasis this offseason.”

Cornerback Devin McCourty, the Patriots’ first-round draft pick, signed a five-year deal worth $13.2 million, with $7.825 million guaranteed, according to his agent, Andy Simms.

New England released injury-plagued linebacker Shawn Crable.