The singer also failed to impress some concertgoers at the TD Garden when she finally arrived on stage, with one describing it as a "joke of a show".
Rihanna was in the city for the rescheduled date as part of her 'Diamonds World Tour'. She cancelled the original Boston concert in March after contracting laryngitis.
A$AP Rocky wasn't available to play as the support act at the new show, meaning fans were forced to wait hours with no entertainment until the 'Stay' star showed up with no explanation for her lateness.
The Mirror reports that Rihanna was watching basketball team the Chicago Bulls take on the Miami Heat.
One fan tweeted: "@rihanna 2-3 hrs late for your show in Boston, huh??! #disrespectful #noexcuse basketball was more important huh?? Don't come back."
Another wrote: "Thank you @rihanna for playing an hour long concert and lip syncing the whole thing. I'm glad u 'balled out' for Boston."
A third concertgoer said: "@rihanna... was three hours late and did a joke of a show!!"
Rihanna appeared unfazed by the criticism, later tweeting: "#BOSTON I will never forget this night!!! I truly have deeper love for you now!!! Thank you for making it extra special!"
It was recently reported that she has split from Chris Brown once again.