But it was still a night of woe for the Hammers for while one new signing was starring, another, Kieron Dyer, was undergoing an emergency operation.
He had been rushed to the local hospital with a double break in his right leg.
Dyer had been bowled over in the tenth minute by a straightforward challenge from Rovers' Joe Jacobson and immediately signalled he was in trouble.
He was given prolonged treatment on the pitch before being stretchered off with his right leg in a support.
Mark Noble took over his midfield role and quickly blasted a shot over the top as West Ham rather anxiously looked for the goal to put them on top.
Bobby Zamora missed an early chance when he headed well over after running through to meet a good ball from Luis Boa Morte.
The goal they wanted came just after the half hour when Rovers captain Stuart Campbell gave the ball away to Hayden Mullins. He quickly teed up a chance for Bellamy to drive in a 25-yard shot.
It was Bellamy's first goal for his latest club and he scored again before the interval this time running on to a long ball from Lucas Neill.
Rovers were getting few chances although Richard Walker got in one header rather too straight and easily collected by Richard Wright.
Rovers stepped up their game in the second half and after throwing on all three subs pulled a goal back through Andrew Williams.
In the 72nd minute he jinked past Danny Gabbidon and knocked a cool goal past Wright.
The Hammers had been hoping to give Dean Ashton his first start since he broke an ankle a year ago training with England. But the striker had to pull out as his wife went into labour and Bobby Zamora started instead.