Giannis Antetokounmpo had a triple-double with 29 points, 21 rebounds and 11 assists for the Bucks but missed two free throws after Reaves’ late three.
The Lakers, who beat the Bucks by one point at home earlier this month, were down 94-75 with eight minutes and 25 seconds remaining in regulation before they began the comeback which keeps them on track for at least a place in the end-of-season play-in tournament (16-19 April).
Milwaukee coach Doc Rivers said his team paid the price for not putting the game out of reach after opening up the double-digit leads.
“When you have a team down 18 points, you have a chance to take that lead to 30 and we didn’t do that,” he said.
“Instead we let it go from 18 to 10, and that gave them hope. It will be a good lesson for us.”
In other games on Tuesday, the Golden State Warriors boosted their hopes of reaching the post-season with a 113-92 away win over the Miami Heat while the Oklahoma City Thunder kept up the pressure on Western Conference leaders the Denver Nuggets with a 119-112 win over the New Orleans Pelicans.