DURHAM, N.C. (AP) — Duke big man Dereck Lively II is entering the NBA draft after one college season.

Lively announced his decision in a social-media post Tuesday.

The lean 7-foot-1 freshman averaged 5.2 points and 5.4 rebounds in 34 games with 27 starts. But he came on in the second half of the year as a rim protector and key to the Blue Devils’ defense, averaging 2.4 blocks on the year to rank ninth nationally.

The highlight came in a home rivalry win against North Carolina in a game that captured how his value was well beyond any scoring production. He had just four points in that one, but was a force with 14 rebounds and eight blocked shots.

That was part of a four-game stretch in which he had 20 blocked shots, and he finished the year with 23 rebounds and eight blocks in two games in the NCAA Tournament.

Lively arrived as the No. 2 recruit in 247sports’ overall top-ranked recruiting class for Jon Scheyer’s first season with the Blue Devils. He helped Duke surge down the stretch to win the Atlantic Coast Conference Tournament.

Lively joins fellow freshman guard Dariq Whitehead in announcing plans to enter the NBA draft.