Cordarrelle Patterson and Marcus Sherels made the Vikings special teams look good last season.

Patterson led the NFL by averaging 32.4 yards per kickoff return, while Sherels finished second in the league at 15.2 yards per punt return. Both set franchise records, and each was a bright spot in a 5-10-1 season.

But the Vikings coverage teams needed some offseason fixing. With a few tweaks, special teams coordinator Mike Priefer hopes to reduce opposing kickoff and punt return yardage from last year.

Priefer, in his fourth season with the Vikings, has emphasized improving kickoff coverage, where the Vikings finished second-to-last in the NFL by allowing 27.1 yards per return. The Vikings finished 14th in punt coverage, allowing 8.8 yards per return, but there's room for improvement there as well.

"That's been a focus really since the offseason," Priefer said. "When we went back and looked at all of our cut-ups, we were very inconsistent."

The Vikings changed a few drills and toyed with personnel groupings throughout training camp on kickoff coverage. During the second preseason game against the Cardinals, Priefer said he used 42 different players on special teams. He typically rotates 20 to 40 players in a preseason game, but Priefer wanted to equip every special teams player who might make the cut for Week 1.

"I think we didn't get enough preparation as we would've liked to in preseason games covering kicks [last year]," kicker Blair Walsh said. "We got some preparation this year, and we're ready to go."

The punt coverage was average but progressed at the end of the season with punter Jeff Locke. The Vikings allowed a little more than 6 yards per punt return during the second half, with eight either downed or out of bounds, and only one touchback.

Locke, now in his second season, has spent the offseason working on directional punting to pin returners. Locke has a strong leg, but Priefer said it's not always beneficial for him to punt as far as he can.

"There's some situations last year where I could've put the ball in a better spot so the guys didn't have such a long distance to cover to get the guy down," Locke said. "It really is a combination of the better I punt, the better we cover."

While Priefer has been hands-on during the offseason, he'll have to step away at the start of the season. He is suspended for the first three games, which could be reduced to two at the team's discretion, following a team investigation of alleged anti-gay remarks.

Zimmer and Priefer never had worked with interim coordinator Joe Marciano, who will temporarily replace Priefer.

"I've coached against him many times and my father has coached against him many times, and there's a great deal of mutual respect," Priefer said.

Priefer has noticed a difference since organized team activities in the spring. The coverage teams will have to prove it against the Rams without him.