When the Bulls trailed by 15 at halftime of Sunday’s comeback win over the Memphis Grizzlies, coach Billy Donovan emphasized one key area of improvement: hand activity. Donovan knows the easiest way to get his team back into any game is to force the opponent into errors. This is where the Bulls have thrived all season — picking off lazy passes, punching away loose balls, outsprinting opponents from one rim to the other. The Bulls forced 16 turnovers in the second half, and the rest followed in stride as they completed a 44-point swing for a 128-107 win over the second-place team in the Western Conference.