If defensive lineman Arik Armstead already has played his last game with the 49ers, the club will have to replace him.

However, it seems unlikely the 49ers would use just one player to fill Armstead’s roles. Armstead was so valuable to the 49ers because he played defensive end on run downs and rushed the passer from defensive tackle.

The combination Armstead provided almost certainly would become a two-person job.

Solomon Thomas can play defensive end in base situations and rush the passer inside, but not with anywhere near the effectiveness of Armstead at either spot. The 49ers also could re-sign Ronald Blair to provide help at defensive end, while giving nose tackle D.J. Jones more opportunities to get after the quarterback.

Jullian Taylor and Kentavius Street could be rotational players along the defensive line, joining DeForest Buckner, Nick Bosa and Dee Ford.

The 49ers own the No. 31 overall pick in the draft. After that, they do not have another selection until the fifth round. Here are some of their options:

Yetur Gross-Matos, Penn State

Gross-Matos (6-foot-5, 265 pounds) has the versatility to play inside and outside. He could flourish in a role similar to Armstead’s. He registered 17 sacks over his final two college seasons. The 49ers might be able to move back and still get him.

“When you’re on the outside you’ve got more space to make a move or use your speed,” Gross-Matos said at the NFL Scouting Combine in Indianapolis. “Inside it’s coming quick, so you’ve got to be alert to that. And those guys usually, they’re a lot bigger and stronger. So you’ve got a double team coming, you try to make that inside move, so you’ve got to be aware.”

Justin Madubuike, Texas A&M

Madubuike (6-3, 293) figures to be selected in the second round. He could be used initially as an inside pass-rusher in nickel situations after registering 5.5 sacks in each of his final two college seasons.

“It's always good as a defensive interior tackle to create pressure on the quarterback, so I take pride in that and I always try to work on that and even get better at that,” he said. “I have a lot of work to do, put my head down and put my left foot forward and keep on working."

[RELATED: How Arik Armstead could return to 49ers after breakout year]

Khalid Kareem, Notre Dame

Kareem (6-4, 268) is on the 49ers’ radar. He met with the club during a formal interview last week in Indianapolis. He has the versatility to play across the line, and he figures to still be available when the 49ers select in the mid-rounds.

Kareem believes his best NFL fit could be as a nine-technique, in the same scheme the 49ers deploy.

“I can be physical at the point of contact,” Kareem said. “A lot of guys don't like to do it. It's something I've been doing for a long time. It's something my coaches asked me, challenged me: ‘You're pretty good but can you be great?’ And that's something I tried to do this season.”

Kareem registered 46 tackles, 5.5 sacks and 10 tackles for loss in 13 games as a senior.