As was widely speculated when it was discovered that Rockstar Makita Suzuki's Blake Young had suffered a broken back in a testing crash at Barber Motorsports Park on June 9, Australian Superbike Champion Josh Waters has been selected to fill in for the injured Wisconsinite in the Mid-Ohio and Laguna Seca rounds of the AMA Pro Road Race championship.The 23-year-old Waters was impressive in his guest ride during the same Barber test in which Young was injured, ending up fourth fastest in the two-day test on a third Rockstar Makita Suzuki, finishing behind Tommy Hayden, Josh Hayes and Ben Bostrom - and ahead of the likes of Jake Zemke, Young and Larry Pegram."My biggest worry was to come over and be three seconds off the pace," Waters said after the test. "Even though Tommy [Hayden] was a little bit quicker, I was happy to get within a second."Waters won the Australian Superbike title last year with five wins and he is currently third in the point standings in the 2010 championship. The Mid-Ohio and Laguna rounds, however, don't conflict with the Australian Series, clearing the way for the young Aussie to make his AMA debut at Mid-Ohio, July 17-18, and continuing at Laguna Seca on July 25, without hindering his chances of defending his title."Firstly, I would like to wish Blake a speedy recovery," Waters said in a team release today. "When I got the call up, I was blown away that the team thought of me to fill in. I know it's not going to be easy as the next two tracks are quite hard, but I know I have the best team behind me. I will try my hardest and I hope I can do a good job for Suzuki and our sponsors, and I also want to thank my team manager, Phil Tainton, for coming with me."Young is hoping to return to action in time for the Virginia International Raceway round in August.