Brian Robb: Joe Mazzulla misses key opportunity in Celtics loss to Lakers

BOSTON — There are probably few teams in the NBA right now looking forward to the All-Star Break more than the Celtics. After 16 games over the past 28 nights, Boston’s starters looked incredibly flat against the Lakers B squad on Thursday night, falling 114-105 despite LeBron James (ankle) and Anthony Davis (hip) ruled out hours before game time with injuries. The Celtics were double-digit favorites for the matchup but came out of the gate as lethargic as we’ve seen all season. The hosts piled up nine first quarter turnovers, a season-high for the quarter this year. Boston’s starters fell behind by as many as nine points in the opening frame with the sloppy start before Boston’s second unit helped…