Ben Spies thinks AMA Superbike rivals Mat Mladin and Jamie Hacking should consider making the switch to the World Superbike Championship, claiming they are capable of 'fighting for wins'.

Debate has raged over the years as to whether AMA Superbike competitors are of a standard to compete at the front of the World Superbike field, an argument partly resolved by Spies' marvellous start to the 2009 season.

His success, along with the AMA series' recent setbacks - such as Honda's factory withdrawal - has prompted some to believe Spies won't be the last rider to make the switch from national to international competition.

It is a challenge Spies, a three-time AMA Superbike Champion, would welcome, claiming arch-rival Mladin and good friend Hacking would acquit themselves well on the world stage.

"We've got some fast guys in AMA that can do some damage too," he told Radio. "Mat is the guy that, in each season, I would go toe-to-toe with. He can win races over here, there is no doubt about that. I'd say these tracks suit my style a little bit more than Mat's, but he can definitely be up front.

"Another guy is Jamie Hacking - the tracks would definitely suit him! He was consistently up there in third place when no-one else in the world was getting podiums on the Kawasaki, so those two guys could be over here and be in the top ten and fight for wins on their day. I don't doubt that at all."

Although Spies plays down claims that Mladin and Hacking would arrive and decimate the opposition, he does say they can add to the 'six or seven guys' who are capable of winning races.

"There are a handful of guys that can come over from AMA and win a couple of races, but what World Superbikes is known for is the depth of the field. It is one of the best championships in racing, not just motorcycles.

"Every time the green flag drops, there are about six or seven guys out there you need to watch for the win. If you run off the track or lose your set-up in the first couple of laps, then you are struggling to climb through the top ten. That's why World Superbike racing is considered the best!"

Australian racer Mladin, a six-time AMA Superbike Champion, has competed in 18 WSBK races since 1992, but has not raced since 2003 when he managed a wild-card pole position at Laguna Seca.

Hacking, who finished 11th on his MotoGP debut for Kawasaki at Laguna Seca last year, is yet to make a WSBK start.