Cape Town - When Rosko Specman runs out onto the field for this weekend's Cape Town Sevens, he will do so knowing that it will be the last time he represents the Blitzboks for some time.

The 29-year-old, like many of his former Blitzboks team-mates, has made the decision to focus on 15-man rugby and he will join the Bulls ahead of next year's Super Rugby season.

While he has been playing 15-man rugby for most of his career - his most recent stint was with the Cheetahs this year - Specman has made a name for himself on the Sevens circuit where he has notched up close to 150 caps, winning an Olympic bronze medal in the process.

"It's going to be a sad one ... I think this will be my last one for the Blitzboks and I'll have to say goodbye to the guys," Specman said in an interview with SARugbymag on Monday.

"I've learnt a lot from the Sevens with small things that you don't pick up in 15s. I think I'll just enjoy myself this weekend.

"I'm excited for my new challenge with the Bulls."

The Blitzboks are pooled alongside Zimbabwe, Samoa and New Zealand for the Cape Town Sevens.