Pretoria - Scrumhalf Jano Vermaak has been released to play for the Blue Bulls with immediate effect.
The Bulls said in a statement on Monday that Vermaak would leave the Lions more than two months before the end of his current contract.
"Jano Vermaak has signed a contract to play for the Vodacom Blue Bulls for the remainder of the Currie Cup season," the union said.
Vermaak, who joined the Lions in 2004, signed a two-year contract with the Bulls last week, but was not expected to link up with his new team until the end of the Currie Cup season.
The 26-year-old scrumhalf was reportedly left to train on his own at Lions practice the day after he signed with their perennial rivals.
He was then dropped from the side to face the Bulls in Pretoria at the weekend.
The Lions went on to win that game 37-26, stretching their lead at the top of the log, while the Bulls were left trailing in bottom spot.