You think LeBron James and the Lakers were gonna let Rihanna down on the night of her birthday celebration???! Hell no!!
RiRi took her superrich Saudi boyfriend to Staples Center on Thursday to cheer on her favorite NBA player on the night after her 31st birthday ... and the team delivered one heck of a gift!!!
Check out the pics of Rihanna and Hassan Jameel in a private box -- going berserk as the Lakers came back from 19 down to beat the Houston Rockets ... one of the hottest teams in the NBA.