Mavericks' Justin Anderson Viciously Blocks Alley-Oop Attempt vs. Celtics

Dallas Mavericks sophomore Justin Anderson had himself a game against the Boston Celtics on Tuesday in the NBA Las Vegas Summer League.

The 22-year-old finished with a game-high 29 points while hitting six of his 12 attempts from downtown in an 88-82 loss. He added 11 rebounds, one steal and a massive block.

When Abdel Nader tried to finish an alley-oop in the fourth quarter, Anderson came out of nowhere to swat the shot away with disdain.

That was angry.