At around 9:40 p.m., a man and woman caught a ride from a bicycle-taxi on Austin and Capitol after they left the Astros game.
As it was heading westbound on Capitol, a driver hit them, then fled, police say.
The woman driving the bike and the man and the woman riding in the back were thrown from it. Authorities said their injuries were significant, but everyone is expected to survive.
All three people were transported to the hospital.
Despite having witnesses, police say no one was able to identify the exact vehicle that hit them.
Anyone with information is asked to call police.