AUSTIN, Texas -- Oklahoma State has sued Texas co-offensive coordinator Joe Wickline for breach of contract, alleging he misled his former employer about his new position at Texas, and the school is seeking more than $593,000 in damages.

According to the suit filed in an Oklahoma district court Oct. 17, Oklahoma State's board of regents asserts that Wickline violated his contractual agreement to pay a buyout fee of $593,487 if he left OSU for a Football Bowl Subdivision offensive coordinator job that did not include play-calling duties.

Oklahoma State is seeking nearly $600,000 in damages from Texas co-offensive coordinator Joe Wickline for breach of contract, alleging he misled his ex-employer about his position with the Longhorns. AP Photo/Michael Thomas

Wickline filed a countersuit this week and says he is indeed calling plays for Texas' offense, according to an Austin American-Statesman report.

The lawsuits are the latest step in a dispute that began in January, when Wickline left OSU after nine seasons to join first-year coach Charlie Strong's staff.

On Jan. 15, Wickline was hired as Texas' offensive coordinator and offensive line coach. Strong said he would call plays.

Texas also hired Shawn Watson, Strong's former OC at Louisville, and gave him the title of assistant head coach to the offense and quarterbacks coach.

On March 18, Strong changed course publicly, clarifying that Watson and Wickline would share play-calling duties and that "the one final voice will be Shawn."

"Wickline is going to be involved in it," Strong said at the time. "He's going to make some calls. Shawn is going to make some calls. When we go down the stretch and we have to have a call made, I think Shawn, because he's been doing it for a long time and I'm comfortable with him."

Six days after Strong made those statements, on March 24, Oklahoma State says it sent a letter to Wickline demanding his payment. Around April 22, OSU again demanded a payment and informed Wickline of its intent to file a breach-of-contract suit.

"It has now come to our attention that you do not have 'play-calling duties,'" OSU athletic director Mike Holder wrote in his March 24 letter to Wickline. "Instead, it appears that your head coach has confirmed that Shawn Watson, not you, will be calling the plays. Thus, in reality it appears you unilaterally and voluntarily terminated the contract to make a lateral move and as such a waiver of the liquidated damages clause of the contract is not triggered."

Watson has consistently been credited with calling Texas' plays on offense this season, but the full extent of Wickline's contributions to play calling is unclear.

Texas players have said in past interviews that Wickline generally oversees the Longhorns' run game. This week, Strong credited Wickline with installing new read-option concepts for the offense, and Watson took credit for scripting the first 15 to 25 plays of the first quarter of games.

In Wickline's tortious interference countersuit, filed in a Texas district court Monday, the coach reportedly claims that OSU has accused Wickline of lying about his position with a misleading job title and that Texas officials are helping him avoid the terms of the contract.

Texas will face Oklahoma State in Stillwater on Nov. 15.