It didn’t take long for the Washington Redskins’ upgraded offensive weapons to make their presence felt Sunday. In their season-opening victory over the New Orleans Saints, the Redskins put up 40 points — 10 more than the previous high by Washington since Mike Shanahan took over in 2010, and the most since a 52-point output in 2005.

Led by wide receiver Pierre Garcon, who recorded four catches for 109 yards, including an 88-yard touchdown, the Redskins’ skill players displayed improved speed and play-making ability — specifically, the ability to gain yards after the catch and turn modest plays into big gains — that the team has sorely lacked.

In their first two seasons under Shanahan, the Redskins averaged just 18.5 points a game. They have lacked an elite-level or even average quarterback. But when evaluating his talent, Shanahan knew that another big reason for the struggles has been a lack of speed.

The Redskins had sure-handed pass-catchers, but they either struggled to get open or were unable to consistently gain yards after the catch.

With Santana Moss slowed by injury last season, Jabar Gaffney became Washington’s leading receiver with 68 catches for 947 yards. But only 184 of those yards (2.7 yards per game) came after receptions. Moss did better, averaging 4.1 yards after the catch, but lacked the same burst that he has had in years past.

The New England Patriots’ Wes Welker, who had more total yards after the catch than any other wideout in 2011, gained an average of six yards after each reception. New Orleans running back Darren Sproles averaged eight.

The Redskins’ yards-after-catch deficit factored into their decision to make their strongest offseason push since Shanahan arrived to improve the overall speed of the offense.

“It was an emphasis since the first day I got here. Sometimes it takes a little longer to get those players, but you have to have speed,” Shanahan said. “You’ve got to have playmakers at all different positions.”

The Redskins now have a wide receiver unit that features newcomers Garcon, Josh Morgan and Aldrick Robinson to go with a resurgent Moss and a healthy Brandon Banks, who was slowed by a knee injury last year. The tight end position includes Fred Davis, who can use his quickness to create mismatches with linebackers, and new addition Niles Paul. At running back, the Redskins hope to take advantage of Roy Helu Jr.’s quickness as a receiver out of the backfield on screens and when he goes in motion to line up as a wideout.

The hope is that the upgrade in speed cures what has been nearly two decades of offensive struggles. Since the 1991 season, when Joe Gibbs’s Super Bowl-winning offense ranked first in the NFL, the Redskins have cracked the top 10 in scoring only twice (eighth in 1996, second in 1999).

And since that 1999 season, when Washington averaged 27.6 points a game, the Redskins have ranked in the top half of the league in scoring only once (13th in 2005). In the other 11 seasons since, the Redskins have ranked an average 23rd in scoring.

If Sunday’s game is any indication, the Redskins finally may be on the right track. Washington was one of five teams to score 40-plus points in Week 1.

Against the Saints, six Redskins recorded at least 10 yards after a catch, and eight different pass-catchers unofficially combined for 204 total yards after catches. Garcon led the NFL with 101 yards in that category, Robinson recorded a total of 30 yards after receptions and Helu tallied 29. The trio ranked among the top 20 in the NFC in that category.

Garcon did all his damage in the first half before injuring a foot. He will test it Wednesday in practice before the team determines whether he can play against the St. Louis Rams on Sunday.

The additional gains in yardage helped the Redskins record 22 first downs (13 through the air) and control the clock. Washington held the ball for 39 minutes 10 seconds while the Saints’ time of possession was just 20:50.

“It’s always nicer when a guy is covered to throw to a bigger body,” Redskins offensive coordinator Kyle Shanahan said last week. “But you’d always much rather prefer that guy to be open, so getting open is the most important thing.”

With his 88-yard touchdown catch — a play on which Garcon caught the ball at the Redskins 39-yard line and ran 61 yards for a touchdown — the wide receiver turned in the team’s longest pass play since 1987 and did something Washington’s pass-catchers had managed only twice last year.

Of the 19 receiving touchdowns the Redskins scored last season, only twice did a player catch the ball in the field and run into the end zone. The first came on a gimmick play — Banks ran a double reverse and then threw the ball downfield to Moss, who caught it at the 10, turned and trotted into the end zone for a 49-yard score. The other came in Week 17, when Helu caught a screen pass and went 47 yards for a touchdown.

The Redskins believe the additions of Garcon, who averaged 5.1 yards after the catch last season, Morgan (6.6) and Robinson (10.0 during his senior season at SMU in 2010) will help change that.

“We just see that we now finally have a lot of guys that can be making plays,” Davis said. “We feel like any play we run, we’re capable of making big plays. That’s what you’ve got to have to be a great offense.”