Wimbledon this week.

American legend Roscoe Tanner has signed an endorsement contract with Blackburne and is using the state-of-the-art Double Strung racquet in the Over-45 division at the All England Club tournament.

Playing with the Blackburne DS107, the larger of two models, Tanner and Bob Lutz defeated Ken Rosewall and Fred Stolle 6-1, 6-4 in the senior event at Wimbledon. Yesterday, however, the pair were eliminated in the Over-45 quarter-finals by Owen Davidson and Cliff Drysdale, 6-3, 6-4.

Tanner has been using the Blackburne -- which has two string beds that come right up to the edge of the frame on each side -- since February and will appear in promotional events for Blackburne and in Pro-Celeb tournaments throughout the US.

The racquet has been the subject of controversy this summer as a number of USTA officials and umpires deemed it illegal. But Blackburne Racquets Inc. CEO Stephen Encarnacao says they are wrong.

"While the racquet may in fact offer playing advantages that other racquets can't, it is most definitely approved for tournament play,'' he said, citing a ruling by the International Tennis Federation in 1995.

The BB2, as the racquet is called, can give a player more top spin, more slice on the serve, error-free lobs and clean volleys, officials say. It sells for $299.

Tanner, a former Australian Open winner who lost to Bjorn Borg in a Wimbledon final, was once acknowledged as having one of the fastest serves in the world.

"The Blackburne has as much if not more power than my old racquet but it gives me a lot more control from both the base line and at the net,'' he said.