Michigan State’s defensive line was already facing some major changes.

Losing the likes of Shilique Calhoun, Joel Heath and Lawrence Thomas, who started a combined 93 games in their careers, meant that there was a prime opportunity for some of MSU’s reserves to finally step up.

Two of them, however, didn’t take advantage of that opportunity.

Michigan State announced late on Monday night that defensive linemen Craig Evans and Montez Sweat both left the program for “personal reasons.” The school didn’t provide any other details in the release.

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It’s a significant loss considering Evans played in all 14 games for the Spartans as a defensive tackle in 2015. The Sun Prairie, Wisc. native earned a more critical role down the stretch and finished the season with 21 tackles as a redshirt freshman. He was named to the All-B1G Freshman Team by BTN.com and ESPN.com.

Sweat, a 6-6 defensive end, was suspended by Mark Dantonio last season for unspecified reasons. He didn’t appear in any games in 2015, but he was listed as a backup defensive end on MSU’s spring depth chart.

Both Evans and Sweat were listed as reserves heading into the spring. Sixth-year defensive tackle Damon Knox is expected to start alongside likely preseason All-American Malik McDowell while Demetrius Cooper and Evan Jones are listed as the first-team defensive ends.

The Spartans will host their annual spring game this Saturday.