DeForest Buckner and Arik Armstead have said they can be a force when they're on the field at the same time.

The two San Francisco 49ers defensive linemen and former Oregon stars didn't get much of an opportunity to play together during the 2016 season, but now they are playing together and showing they are capable of anchoring the defense.

Buckner and Armstead helped the 49ers post a strong defensive effort during the first half of their preseason game against the Minnesota Vikings Sunday. The 49ers held the Vikings first-team offense scoreless in the first half.

"Our defensive front seven is the focal point of the team," Armstead told reporters after the game. "It's going to go how we go. If we stop the run and pressure the quarterback, good things will happen."

Buckner, seeing his first game action since aggravating an ankle injury two weeks ago at Kansas City, sacked Vikings starting quarterback Sam Bradford on the second play from scrimmage in the game. He finished with three tackles. Armstead also sacked Bradford, posted two quarterback hits and drew a holding penalty that was declined.

Armstead missed eight games with a shoulder injury in 2016, but he's healthy. Buckner played in 15 games and led the NFL in snaps in 2016, when he was on the field for 1,108 plays. His 1,008 snaps on defense was second only to New York Giants defensive end Olivier Vernon (1,054) in 2016.

The two have shown what they are capable of accomplishing for one half. The question is can they produce consistently during the regular season. If they can, the 49ers defense will be much better compared to 2016, when they were ranked last in total defense.

-- Geoffrey C. Arnold | @geoffreycarnold