The Washington Redskins have been extremely fortunate on the injury front this season, but yesterday they had concerns about tight end Stephen Alexander and linebacker Greg Jones as preparations began for Sunday's game in Detroit.

Alexander's strained hip flexor isn't improving, and team officials fear his role against the Lions could be limited. Jones, meantime, has a sprained lower back, and coaches will spend the next few days making contingency plans in case he's unable to play.

Alexander has been playing with the hip injury for several weeks and has only one catch in the last two games. He underwent an MRI exam yesterday, and trainer Bubba Tyer said the test revealed some inflammation--but no acute tear--of the muscle around the upper thigh.

The Redskins don't have the luxury of giving Alexander the rest necessary for the injury to heal completely. Tyer said he's hopeful Alexander could practice by the end of the week and play some on Sunday.

Alexander felt better than the Redskins expected yesterday, but team officials weren't particularly optimistic he'll be at full speed by Sunday. Having Alexander sidelined or limited would restrict the Redskins' offense because the team's other two tight ends, Mike Sellers and James Jenkins, are used more as blockers than receivers. Sellers did have a touchdown catch in Sunday's overtime win over the Philadelphia Eagles on a deflected pass.

"I think Stephen will be able to play," Coach Norv Turner said. "If he's not able to practice Thursday or Friday, we'll limit his role."

Jones underwent surgery following last season to have a herniated disk in his back repaired and has played with a hernia this season. He injured his lower back in the first quarter Sunday. Tyer said he doesn't think this injury is related to the previous back problems.

"I just don't know at this point," Jones said. "We're going to try to find out if it's related. We'll just have to see how it goes."

The Redskins' other starting outside linebacker, Shawn Barber, is playing with a sprained shoulder, and free safety Leomont Evans suffered a bruised foot Sunday. Eddie Mason got some playing time in Barber's place Sunday, but Barber said he expects to remain in the lineup.

"It's not as bad as when I first hurt it," Barber said. "It's a nagging thing. I don't foresee it keeping me out of any games."

If Jones is unable to play against the Lions, the Redskins will use either James Francis or Mason in his place. With Barber also hurting, the Redskins have the fallback plan of using veteran Kurt Gouveia at middle linebacker and moving Derek Smith from middle to outside linebacker.

The Redskins yielded a pair of 91-yard touchdown drives in the second half to the Eagles, but continued their gradual defensive improvement. They moved up another notch in the NFL's defensive rankings, from 30th to 29th. Since the hiring of Bill Arnsparger four games into the season to assist defensive coordinator Mike Nolan, the Redskins have surrendered 5.4 fewer points and 101.6 fewer yards per game.

"You'd like to be able to do what needs to be done," Arnsparger said. "We made some errors [Sunday]. I felt like we needed to be better."

The Redskins basically are using the same defensive schemes they used earlier in the season. Jones said the defensive game plans were simplified after Arnsparger's arrival.

"We were ranked last," Barber said. "You can't go backwards from that. We've just taken the attitude that we're not worried about our ranking.

"We're just trying to help the team win . . . Early on, guys were so eager to make plays, they didn't do what they were responsible for first. Now guys are concentrating on doing their jobs."