The San Francisco 49ers worked out three defensive linemen on Tuesday. Two of those players were former Atlanta Falcons defensive end Tyson Jackson and former Pittsburgh Steelers defensive end Ricardo Mathews.

The visits prompted speculation that the 49ers might be gearing up for a trade and looking for players to fill a potential void should the team deal a player. While a trade is not necessarily out of the realm of possibility, Matt Maiocco of NBC Sports Bay Area was quick to remind everyone that the 49ers currently have two vacant spots on their 90-man roster. The 49ers are likely just searching through potential candidates to fill those spots as the team heads into its third preseason game.

General manager John Lynch was open with the media last week while the Denver Broncos were in town and did state that he did have "some of those discussions" with his Broncos counterpart – John Elway. Although, it would appear that nothing moved beyond the discussion phase for now.

The 49ers have two vacant roster spots because defensive back Jimmie Ward remains on the physically-unable-to-perform list. Although, Ward was worked out by the 49ers on Monday and Tuesday and could be activated as early as Wednesday, which would still leave one roster spot open. Last week, the 49ers waived injured linebacker Jayson DiManche and placed rookie linebacker Donavin Newsom on injured reserve. The team filled one of those spots with the return of linebacker Shayne Skov.

It is still odd that the 49ers appear to be focusing on the defensive front seven, which is one of the few areas on the team considered to be a strength as far as depth goes.

"The 49ers have an abundance of defensive linemen, or players capable of rushing the passer from a position along the defensive line," wrote Maiocco on Tuesday, "such as DeForest Buckner, Arik Armstead, Solomon Thomas, Earl Mitchell, Elvis Dumervil, Aaron Lynch, Chris Jones, Tank Carradine, Quinton Dial, Ahmad Brooks, Eli Harold, Ronald Blair and D.J. Jones."

Of that list, injuries prevented Buckner, Blair, and Lynch from playing against the Broncos. That may have been a contributing factor in Tuesday's visits.

The 49ers have spent a great deal of draft capital in recent years to revamp the defensive line. They have used their top pick in each of the last three drafts to select defensive linemen. Armstead was selected in 2015, Buckner in 2016, and Thomas this past April. D.J. Jones is another rookie while Mitchell and Dumervil are new offseason additions.

The potential activation of Ward and the signing of one of the players who was worked out would fill the 49ers' 90-man roster.

Shanahan is scheduled to meet with the media on Wednesday at 12:15 p.m. and will undoubtedly be asked about the team's roster plans.