As a freshman in 2001, he went 10–3 with a 5.08 ERA and 56 strikeouts in 78.2 innings pitched to lead the nationally ranked Demon Deacons in wins.
On March 28, 2003, Sleeth tied the NCAA record for consecutive victories against Duke with his 26th straight win.
The 26 consecutive wins left him tied with former Brigham Young University pitcher Scott Nielsen, who established the mark in the 1978 and 1982-1983 seasons.
In 2019 Sleeth was inducted into the Wake Forest Sports Hall of Fame for his accomplishments as a Demon Deacon.
Sleeth would become the 3rd overall pick in the 1st round in the 2003 Major League Baseball Draft for the Detroit Tigers.