The loss of scrumhalf Jano Vermaak would create opportunities for promising young players in his squad, Lions coach John Mitchell said on Wednesday.
Vermaak, who joined the Lions in 2004, signed a two-year contract with the Bulls on Tuesday.
"You need to look at the positives in situations like this," Mitchell said.
"Sure, it's a blow to lose a player of Jano's calibre, but now we can look to the future.
"At the moment those (future) players are Michael Bondesio and Rudy Paige, who I see great potential in, and we can start investing in and focussing on them and developing other future scrumhalves within the Lions."
Vermaak is set to join the Bulls at the end of the Currie Cup season, but Mitchell said he would need to make way for younger players for the remainder of the season.
"Jano will still be with the Lions for the rest of the season, but I will use this as an opportunity to develop my future players and utilise Jano in case of injuries," Mitchell said.
Vermaak had given little warning that he was leaving the Lions, and Mitchell said he was disappointed to lose him to their Pretoria rivals.
"To say that we were blindsided by Jano's decision to leave the Lions would be an understatement," he said.
"I can't say we're very pleased about the situation, but you can't retain players if their hearts are elsewhere.
"I wish Jano success in the future and thank him for his contribution."
Lions chief executive Manie Reyneke said they had "done everything" to try and retain Vermaak's services.
"He's been a very influential player who has served the Lions well over the years," Reyneke said.
"We are sad to lose him, but we understand his choice to leave after having discussions with him, and we wish him all the best."
Vermaak said his decision to move to Pretoria was not based only on rugby commitments.
"I've been at the Lions for such a long time - nearly six years - and I just need a change and a new challenge at this point," Vermaak said.
"This wasn't just a rugby decision, but also a business one.
"There are some business opportunities in Pretoria and I need to start looking at my life after rugby."
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