AUSTIN, Texas — After landing his second consecutive Top 10 recruiting class this week, Texas coach Tom Herman learned some of his most important recruiting was just beginning.

In his own quarterback room.

According to two sources close to the situation, Casey Thompson has joined fellow redshirt freshman quarterback Cameron Rising in entering his name into the new, NCAA transfer portal to re-open his recruitment and explore transfer options.

According to sources, Herman spent Thursday and Friday trying to convince his two, redshirt freshmen quarterbacks not to leave. But the two, four-star prospects signed in 2018 wanted to explore their options.

The NCAA transfer portal, which launched for the first time in October, allows student-athletes to re-open their recruitment while still maintaining the possibility of staying at their current school.

Both Rising and Thompson are now home with their families for Christmas, where they will continue to contemplate their next moves.

Texas leaves Dec. 27 for a New Year’s Day Sugar Bowl matchup with Georgia, which had backup quarterback Justin Fields enter his name into the transfer portal last week as well.

Texas had no official comment on Rising or Thompson entering their names in the transfer portal.

A UT spokesman said Saturday Rising and Thompson have been practicing with the team and plan to be with the Longhorns in New Orleans for the Sugar Bowl.

According to sources, Rising, a pro-style passer, is concerned about the structure of the Texas offense and current quarterback Sam Ehlinger’s 143 rushing attempts, while Thompson, who served as Texas' scout-team quarterback, is concerned about where he fits into the pecking order at quarterback.

In January, Texas was set to have five scholarship quarterbacks: sophomore Sam Ehlinger, who accounted for 38 touchdowns this season (25 TD passes with five interceptions with 13 rushing TDs); junior Shane Buechele, who redshirted this season and graduates in May; Rising; Thompson; and incoming, early enrollee freshman Roschon Johnson, who just signed with Texas on Wednesday.

Ehlinger's development during his sophomore season, including a Big 12-record 308 pass attempts without an interception for the 9-4 Longhorns, has complicated Herman's ability to keep his current quarterback room in tact.

There's also been speculation Buechele, who has two years of eligibility remaining after redshirting this season, might pursue a graduate transfer before next season. Buechele started every game for the Longhorns as a freshman in 2016, defeating Notre Dame in his first college start, before losing the starting job to Ehlinger. But Buechele started seven games in 2017, in large part, due to injuries to Ehlinger.

This season, Buechele relieved Ehlinger after Ehlinger suffered an AC joint sprain in his throwing shoulder on the opening drive against Baylor and helped lead Texas to a 23-17 victory. Buechele also played the second half against Iowa State, going 10-of-10 passing in a 24-10 victory after Ehlinger aggravated his shoulder injury. Rising and Thompson haven't gotten any snaps through the first 13 games of 2018.

Sources said part of Herman's recruiting message to Rising and Thompson was based on the coaches not knowing exactly what they had in Ehlinger and Buechele heading into the 2018 season. But then Ehlinger had a breakout season and, as of right now, is certainly the odds-on favorite to be UT's starter heading into 2019.