DETROIT (AP) It was only a preseason game, so take it with the appropriate level of skepticism. But for many casual NFL fans, the first image of the Detroit Lions this season was their pass rush swarming Robert Griffin III last month against Washington.

Looked pretty good without Ndamukong Suh.

As the Lions try to return to the playoffs after losing in the opening round last season, much of the focus will be on how their defensive front deals with the loss of Suh. The star defensive tackle departed via free agency, leaving a major hole to fill on a defense that was one of the league's best in 2014.

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''Whenever our defense steps on the field, we anticipate that we should play well,'' defensive coordinator Teryl Austin said not long after that exhibition game against Washington. ''We know we have a lot of work to do.''

Suh and Nick Fairley both left as free agents, but the Lions quickly traded for defensive tackle Haloti Ngata from Baltimore. Ngata has dealt with a hamstring injury during the preseason, but he was activated last week. So was Joique Bell, who has had injury issues of his own lately.

The Lions made the playoffs as a wild card last year in coach Jim Caldwell's debut season with Detroit. The offense never quite clicked as well as Lions fans had hoped, but Matthew Stafford and Calvin Johnson are back for another go-around this year.

It was the defense, led by Suh, linebacker DeAndre Levy and defensive back Glover Quin, that made Detroit a playoff team, and that unit now has to move on without a couple of its key players from last season. Ngata was brought in to help, and the Lions also signed free agent defensive tackle Tyrunn Walker. Second-year defensive tackle Caraun Reid has shown some potential, although he was also limited by an injury this preseason.

Defensive end Ziggy Ansah had 15 1/2 sacks in his first two seasons, so the Lions definitely have pass-rushing threats still on the roster.

Detroit opens the season at San Diego on Sunday.

Here are a few more things to watch for with the Lions in 2015:

ABDULLAH'S EMERGENCE: Detroit cut RB Reggie Bush in the offseason and drafted Ameer Abdullah in the second round. It looked like Abdullah would provide some much-needed help for Bell in the backfield, but with Bell's health not totally certain, it's possible Abdullah could play an even bigger role as a rookie.

OFFENSIVE LINE MAKEOVER: Stafford was sacked a career-high 45 times last season, and the Lions parted ways with C Dominic Raiola and G Rob Sims. Detroit also used its first-round pick on G Laken Tomlinson and traded for OL Manny Ramirez.

TULLOCH'S RETURN: Lions LB Stephen Tulloch missed most of last season after he injured his knee celebrating a sack in a September game. Detroit's defense did fine without him, but the veteran's presence will certainly be welcome.

EXTRA RECEIVERS: Golden Tate was terrific last year in his first season with the Lions, providing some much-needed support for Johnson at receiver. Beyond that, it's not clear who else the Lions can count on. Detroit cut WRs Ryan Broyles and Jeremy Ross and TE Joseph Fauria - and TE Eric Ebron caught only 25 passes last season after the Lions drafted him in the first round.

Detroit also drafted receiver TJ Jones last year, but he didn't play as a rookie because of a shoulder injury. He turned a short pass into a 64-yard touchdown to help the Lions beat the Buffalo Bills in a preseason game.

HIGHER EXPECTATIONS: Ever since the Lions made the playoffs in 2011 for the first time with Stafford, Johnson and Suh, Detroit fans have wondered when the next step would come. It took three years for the team to make it back to the postseason, and the Lions lost a hard-fought game at Dallas in the opening round.

Detroit has won only one postseason game in the past half-century, and with Stafford now in his seventh season and Johnson turning 30 this month, there's some pressure on the Lions to advance deeper into the playoffs.

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