Dorial Green-Beckham was labeled the No. 1 national recruit in the 2012 class, landed at Missouri but found trouble and, two years later is petition for the right to play at Oklahoma without sitting out the customary transfer season required under NCAA rules.

A newcomer of DGB's caliber is difficult to come by, but there are several first-year players in every program arriving with expectations to star from the opening kickoff.

That includes Johnny Manziel's former backup and his heir apparent.

Matt Joeckel transferred from Texas A&M to TCU, and Kyle Allen could be the second coming for the Aggies, and the first true freshman to start at quarterback for the program since World War II.

The Sports Xchange asked its college football correspondents to narrow the plentiful list of such players to watch, selecting the top newcomers in the Big 12:

WR KD Cannon, Baylor: Steps into the role Baylor fans hoped to see Robbie Rhodes fill last season -- that of immediate-impact receiver. The offense proved to be too complex for Rhodes to step into right away and he struggled to a 10-catch 157-yard season. That suggests that freshmen will be a long shot to come in and play. However, with Rhodes dismissed from the team and Clay Fuller hurt in preseason practice, the window of opportunity is open for Cannon.

WR Allen Lazard, Iowa State: A local product from Urbandale (Iowa) was a high school All-American and the most high-profile recruit head coach Paul Rhoads has landed. Lazard comes in built to play immediately with a 6-foot-5, 221-pound frame. He had 2,349 receiving yards and 34 touchdowns in his high school career.

WR Nick Harwell, Kansas: An All-MAC selection (first-team in 2011) each of his three seasons at Miami, Ohio, Harwell has the tools to revamp the Kansas passing game, which has produced just three touchdown receptions from wide receivers in two seasons under Weis. Harwell has incredible hands, which should help make him a sure target for Cozart.

DT Terrell Clinkscales, Kansas State: Assuming the junior-college transfer is academically eligible, he should provide considerable brawn (6-4, 315) to the middle of the defensive line. Clinkscales' transition to the Kansas State system will be intriguing since it will be his third school in as many years after playing for two different juco programs. He recorded 7.5 tackles for loss among 40 stops last season for Dodge City (Kan.) C.C. The run-stopper originally committed to Nebraska.

FB Dimitri Flowers, Oklahoma: The true freshman arrived in January and immediately drew comparisons from coaches and teammates to Trey Millard, the Sooners' departed fullback/tight end/running back. Flowers figures to take Millard's role as the versatile playmaker on the offensive side. He showed why in the spring game when the first four plays were intended for Flowers.

FL Tyreek Hill, Oklahoma State: Use as many adjectives as you want to describe the potential Hill provides after transferring from Garden City (Kan.) C.C. in time to participate in spring drills. He happened to also compete in indoor track and captured the Big 12 title in the 200-meter. Owns the second-fastest high school time in the 200 (20.14) in U.S. history. Generated 532 yards receiving and 659 yards rushing a year ago while displaying his versatility in juco.

WR Armanti Foreman, Texas: When Texas WRs Kendall Sanders and Montrel Meander were suspended from the team this summer, it left that position razor thin. But the good news for Texas fans and Horns freshman Foreman is that it means an opportunity for instant impact. Foreman showed the combination of size, speed and hands to make him one of the most prized wide receiver recruits in the nation as he was ranked as the 110th overall prospect and the 26th best wide receiver. The Horns need him to live up to that high billing in a hurry.

QB Kyle Allen, Texas A&M: Though the job is not yet his, Allen will attempt to become the first true freshman to start at quarterback for the Aggies since World War II. Whether he starts or not, Allen figures to get his shot running the show for Texas A&M. Allen passed for more than 8,000 yards and 86 touchdowns in high school. He's not the runner that Johnny Manziel was, but that could just take the pressure off of him to be Manziel-like.

QB Matt Joeckel, TCU: OK, if he's the favorite to win the quarterback battle, Joeckel must take the competition another step and give the Horned Frogs consistent punch they have lacked since joining the Big 12. That depends greatly, of course, on the contributions of teammates. In particular, the offensive line must develop with the possibility that group could field up to four new starters. Joeckel, a graduate transfer from Texas A&M, played in five games each of the past two seasons as Johnny Manziel's understudy.

DT Keland McElrath, Texas Tech: He joined the Red Raiders in time for spring drills, which enabled McElrath to get a jump over other juco linemen who were recruited to bolster the defensive line. Considered a powerful run-stopper. McElrath had difficulty adjusting to a fast pace during spring camp, but used that experience to get into better shape. Other candidates exist too and will provide depth up front.