Considered only a two-star recruit by Rivals.com, Gilyard was not ranked among the nation’s best wide receiver prospects. He committed to Cincinnati on February 2, 2005.

Gilyard played cornerback as a freshman in 2005. He finished the season with seven tackles. As a sophomore in 2006 he was redshirted due to academic reasons. In 2007 Gilyard started 7 of 12 games at wide receiver for the Bearcats. He finished the season with 36 receptions for 536 yards and 3 touchdowns. In 2008, he recorded 81 receptions for 1,276 yards and 11 touchdowns. As a senior in 2009 he was an All-American after he had 87 receptions for 1,191 yards and 11 touchdowns. He was selected to play in the 2010 Senior Bowl and was the offensive player of the game after he had 103 yards on five receptions and a touchdown.

Gilyard was drafted in the fourth round with the 99th overall pick by the St. Louis Rams in the 2010 NFL Draft. On June 28, 2010, Gilyard signed a four-year $2.32 million contract with a signing bonus of $552,000.

He was released by the Rams in the final cutdown after the fourth preseason game in the 2011 preseason.

The New York Jets claimed Gilyard off waivers on September 4, 2011. However, he was waived by the Jets on September 9.

Gilyard worked out for the Philadelphia Eagles in September 2011 and met with the team again on January 5, 2012. He was signed to a futures contract the following day. On August 31, 2012 Gilyard was released by the Eagles. On September 11, 2012, he was signed by the Eagles. In six games with the Eagles, his only stats were two punts returned for 15 yards. On November 23, 2012, he was released to make room for Greg Salas.

Gilyard was signed to the Jets’ active roster on November 28, 2012. The Jets waived Gilyard on December 24, 2012. In two games with the Jets, he caught two passes for 15 yards.

Gilyard was signed by the Kansas City Chiefs on February 9, 2013. On July 25, 2013, Gilyard was released by the Kansas City Chiefs.

On October 3, 2013, Gilyard signed with the Montreal Alouettes.

On October 31, 2013, Gilyard was assigned to the Jacksonville Sharks of the Arena Football League.

During the 2014 season, he caught two passes for 16 yards.

On June 1, 2016, Gilyard was activated by the Sharks. On June 22, 2016, Gilyard was placed on recallable reassignment.

On February 28, 2017, Gilyard signed with the Monterrey Steel of the National Arena League (NAL). On June 21, 2017, Gilyard was released.

On December 6, 2017, Gilyard signed with the Massachusetts Pirates of the National Arena League. During the 2018 season, Gilyard recorded 69 receptions, 747 receiving yards, and 19 TDs. Gilyard re-signed with the Pirates for the 2019 season and produced 84 receptions, 950 receiving yards, and 29 TDs. Gilyard was named to the 1st-Team All-NAL for the 2019 season.

In 2019, Gilyard joined the football coaching staff at Nichols College in Dudley, Massachusetts. He will serve as Defensive Backs coach for the Bison, whom are an NCAA Division III program in the Commonwealth Coast Conference.