New England wide receiver Reche Caldwell dropped two passes in the 2006 AFC Championship Game – one in the end zone that would have been a touchdown and the other in the flat that would have produced a first down – and the Patriots suffered a rare second-half collapse in losing to the Indianapolis Colts.

It bothered Patriots coach Bill Belichick that his passing offense lacked big plays in 2006. So he traded for Randy Moss. It bothered Belichick even more that his Pro Bowl quarterback Tom Brady didn't have a trusty target when he absolutely needed a completion. So he traded for Wes Welker.

Moss gave the 2007 Patriots the big plays, setting an NFL record with 23 touchdown receptions and finishing second in the league with 1,493 receiving yards.

But Welker gave the Patriots the important plays, leading the Patriots and ranking sixth in the NFL with 26 third-down receptions. Welker became Brady's favorite target, leading the NFL with 112 receptions. He made the catches that kept the touchdown drives alive for Moss.

Belichick revamped his receiving corps, also signing Donte Stallworth in free agency. All three posted 100-yard receiving games as Brady took the receiver that defenses gave him.

Moss opened the season as the focal point of the offense, catching 100 yards in passes in each of his first four games and scoring seven touchdowns. That forced weekly double coverage of Moss and the emergence of Welker.

Welker lit up the Cowboys in October with 11 catches for 124 yards and two touchdowns, then roasted his old team, the Miami Dolphins, the following week with nine catches for 138 yards and two touchdowns.

If a defense plays straight up on New England's three-wide package, Moss will hammer single coverage. If a defense doubles Moss, it's Welker who runs wild in the slot. It's the defense's choice.

It's easy for a defense to lose track of Wes Welker. An entire league lost track of him in 2004.

Welker was a graduating senior that year but was not deemed one of the 323 best draft prospects invited to the NFL scouting combine.

Forget that Welker caught a Texas Tech-record 259 passes and set an NCAA record with eight career punt returns for touchdowns. Too small, said the scouts. Too slow, said personnel directors.

Welker went undrafted but signed with the San Diego Chargers. He was cut during his rookie season and was signed by the Miami Dolphins. He spent his first two NFL seasons strictly as a kick returner.

The Dolphins finally started throwing him passes in his third season, in 2005, and Welker went on to lead Miami in receiving in 2006. His ability as a slot receiver attracted the Patriots, and he went on to lead the NFL in receptions in 2007.

Welker is the same receiver for the Patriots he was at Texas Tech – tough, crafty and dependable. He runs crisp routes and is fearless across the middle. When he gets hit, he holds on. No wonder Brady throws him the ball.

According to Stats Inc., Brady threw Moss 159 passes, and Moss caught 98 of them. He threw Welker 145 passes, and Welker caught 112 of them. Moss had nine drops, and Welker had four. Brady counts on Moss to make the big plays, but he counts on Welker to make the sure plays.

Welker isn't going to run by cornerbacks on speed routes. That's the role of Moss and Stallworth. Welker excels at routes with cuts. That's where he gets his separation from defenders, on the quick ins and quick outs. He averaged only 10.5 yards per catch with a long of only 42. Moss had six receptions longer than that.

With defenses focusing on Moss and on preventing the big play, it's easy to lose track of Welker underneath. Brady makes defenses pay when they do.