Adonis Alexander will join the Redskins’ defensive backfield. (Chris O’Meara/Associated Press)

The Washington Redskins selected Virginia Tech defensive back Adonis Alexander with a sixth-round pick in the NFL’s supplemental draft Wednesday. The move adds to the team’s depth in the defensive backfield and costs it a sixth-round pick in the 2019 draft, per league rules.

The 6-foot-3, 197-pound Alexander is known for his versatility and could line up at cornerback or safety while bringing size to the position group. He had 27 tackles, one sack, one interception and four pass breakups in eight games as a junior in 2017. The Charlotte native picked off seven passes during his three-year career and is a long-armed defender who can get physical with wide receivers at the line of scrimmage.

During his time at Virginia Tech, Alexander, 21, had a 2016 marijuana arrest and faced academic issues. He was suspended for three games during his college career. He entered the supplemental draft after being ruled academically ineligible for what would have been his senior season.

“I can honestly say, the past year, maturity has been my biggest thing,” Alexander told NFL.com in June. “I have been improving on discipline. Discipline is a big thing for me now, because nothing can really be done without discipline. And I understand that now.

“I thought I was untouchable, doing stuff I wasn’t supposed to do, but as I got older, I realized the other opportunity that I was messing up. Back then, I was probably a more in-the-moment guy. I didn’t really look ahead. But I can honestly say as I mature, I begin to think about my future before I make a decision.”

Alexander is the third Virginia Tech player the Redskins have drafted this offseason. In April, the organization took defensive tackle Tim Settle in the fifth round and cornerback Greg Stroman in the seventh round. Defensive backs coach Torrian Gray is a former Virginia Tech player who also coached the Hokies’ defensive backs for 10 seasons.

To make room for Alexander on the roster, the Redskins waived punter Sam Irwin-Hill after signing him as a free agent in March. Alexander is the first player the Redskins have taken in the supplemental draft since 2009, when they added Kentucky defensive end Jeremy Jarmon. Only one other pick was made Wednesday: The New York Giants added Western Michigan cornerback Sam Beal in the third round.

The Redskins have had plenty of transition in the defensive backfield this offseason after trading Kendall Fuller — another former Virginia Tech player — to the Kansas City Chiefs as part of the deal that brought quarterback Alex Smith to Washington. Bashaud Breeland, a starter in 2017, signed with the Carolina Panthers, but he failed his physical and remains unsigned. Washington then added former Dallas Cowboys cornerback Orlando Scandrick.

In a supplemental draft profile, NFL.com analyst Bucky Brooks touted Alexander’s ability to “smother receivers at the line of scrimmage” and “routinely pin receivers to the sideline with the ball in the air to minimize the target area for the quarterback on downfield throws.” On the downside, Brooks noted the defensive back’s game is still a work in progress and that he needs to “refine his footwork” and improve his movement when not running in a straight line.

The Redskins begin training camp July 26 in Richmond.