RENO, Nev. (AP) — Coach Brian Polian's first recruiting class at Nevada is heavy on defense, including four speedy defensive backs and a star linebacker who is the nephew of future NFL Hall of Famer Junior Seau.Ian Seau is among 21 players who signed formal national letters of intent on Wednesday to play for the Wolf Pack.The 6-2, 250-pound Seau started his career at Kansas State. Last year, he was a junior college All-American at Southern California's Grossmont College, where he had 74 tackles, 25.5 tackles for loss, 18 sacks and forced three fumbles in 10 games.Nevada also landed Beau Hershberg, a 6-2, 230-pound linebacker from California's Granite Bay High. Scout.com listed him as one of the top 150 prospects on the West Coast. He told the Reno Gazette-Journal he chose Nevada over Navy and Air Force.Polian was special teams coach at Texas A&M before he was hired last month after Chris Ault retired in December."Looking at this class overall, I'm really excited," Polian said Wednesday. "To think we could put this group together in less than a month is really exciting."The class is heavy on linebackers and defensive backs because the Wolf Pack lose six of its seven starters at those positions.The new cornerbacks include D'Andre Fuller, a highly recruited prospect from Arlington, Texas; Elija Mitchell, the reigning 200 meters champion in the state of California; and Tere' Calloway, a two-time state all-state selection from Seattle Prep High School who said he had offers from nearly two dozen schools.The 5-foot-9, 165-pound Mitchell of Corona, Calif., runs 100 meters in 10.5 seconds and 200 meters in 21.1. He was recruited by Boise State, Colorado State and Army and had an offer to run track at Wisconsin.Calloway's offers include Wisconsin, Texas Tech, Colorado and Purdue.