Zac Efron checks his phone while filling up his car at a gas station on Monday (January 31) in Hollywood.

The night before, Zac was one of the handful of celebs who watched the Boston Celtics beat the L.A. Lakers 109-96 at Staples Center.

Zac sat courtside, where he shook hands and chatted with Lopez Tonight host George Lopez.

10+ pictures inside of Zac Efron at a gas station…