[3] As a sophomore at Arizona State University he earned first-team All-Pac-10 honors as a punt returner and also had 29 catches for 360 yards and six touchdowns.

Williams finally became a regular starter as a senior, leading the Sun Devils with 57 catches for 815 yards and eight touchdowns in 2009, in addition to garnering first-team All-Pac-10 as a wide receiver by PhilSteele.com, and second-team All-Pac-10 as a punt returner.

[10] Williams caught 16 passes in a six-game stretch late in the season after his role increased with injuries to 49ers wide receivers.

[11] In the playoffs, Williams caught two passes and made a key block on quarterback Alex Smith's go-ahead 28-yard touchdown run in a 36–32 divisional round win over the New Orleans Saints.

[11][12] With Ted Ginn Jr. injured, Williams started at wide receiver and performed punt returns in the 49ers' 20–17 loss in the NFC championship game.

He lost two fumbles returning punts, including one in overtime that led to the game-winning field goal by the New York Giants.

[17] Williams signed with the Denver Broncos in 2014, however on August 1, 2015, he ruptured his Achilles tendon in his left leg, and announced he would miss the entire 2015 season.