Ben Spies went a long way to prove the hype surrounding him in 2009 isn't without reason as he joined an elite group of riders that have won a race on their World Superbike debut.

A day of two halves for the Texan, Spies endured a disastrous first race, but made amends in the second after coming out on top in a heated battle between himself and Noriyuki Haga.

His win, the first for an American since 2002, means he enters the history books as one of the few people to take a victory on their maiden weekend, while his win also signals a successful first outing for the uneven-firing, or 'big bang', Yamaha R1

Starting both races from pole position, Spies began his first ever WSBK race well when he slotted into third position heading into the second turn. However, when Max Biaggi ahead ran wide, Spies had nowhere to go but around the Aprilia and onto the grass.

Dropping towards the back of the field, Spies' misery was compounded when a problem for another rider further around the first lap caused him to clip Ruben Xaus and take another trip off the circuit.

Although Spies enjoyed a quick pace from then on, his fight back was only good enough for 16th, one position out of the points. Still, he was philosophical about his chaotic first WSBK racing lap.

"I just had to put that first race out of my mind," Spies said. "It was no one's fault, I was just in the wrong place at the wrong time in both incidents. It was frustrating because I knew I had the speed to run up front. Fortunately I had another race and it made me that much more determined."

With another chance to make for victory from the top spot, Spies started race two well to snatch the lead from Biaggi at turn two, but immediately found himself under pressure from race one winner Haga, who was making another excellent getaway from 13th on the grid.

The Japanese rider assumed the lead on lap five and led for the majority of the way, despite a quick change of positions midway through the race when Spies edged through, only to make an error shortly afterwards.

Working with Haga to move away from the chasing pack, Spies' decision to play the waiting game paid dividends when his rival's tyre began to wane. Taking back the lead with four laps remaining, Spies would eventually ease to a comfortable and emotional victory.

"As the race progressed Nori and I were trying to work together to gap the rest of the field," Spies explained. "It worked out well in the final part of the race and it was pretty much him and me going for the win. I think in the end I just hung it out a little more [than Haga] when the tyres started going off.

"It's great to get a win under my belt," Spies concluded. "It takes a little pressure off. I feel pretty fortunate to come out of here in fourth after what happened in the first race. Now we go to Qatar and see if we can start chipping away at Nori's lead."

Despite his first race problems, Spies comes away from the first round in fourth position overall, albeit 20 points adrift of Haga.