Marcus Smart is a very angry man after playing for a Boston Celtics team which has lost four of their last five games.

The 24-year-old, one of the premier perimeter defenders in the NBA, has been unable to help his team overcome their struggles this season but has offered some very blunt advice.

Smart was said to be very emotional after the Celtics' loss to the Portland Trail Blazers on Sunday night. And teammate Marcus Morris revealed the guard's frank message to the team that came in the wake of him storming into the locker room.

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“Smarty is an emotional guy,” Morris told Adam Himmelsbach of the Boston Globe following the loss. “What he said was real. He said we’ve got to fix this [expletive]. He said, ‘It’s not OK. It’s not OK. We need to fix it.’ And I agree with him, 100 percent.”

Smart was just as irate after Boston lost to the Utah Jazz on Friday.

“You gotta wanna guard. That’s what it comes down to," he stressed.

“We’re letting guys that we know are going to do certain things do those things. That’s a slap across Brad’s face and this coaching staff who spends countless hours, countless days, preparing us and giving us the tools that we need to go out there and to cut that off.”

The Celtics are currently sixth in the east after a shocking 7-6 start and cannot afford to lose much more ground, with the Toronto Raptors and Milwaukee Bucks on a tear so far this season.

"We needed this," star point guard Kyrie Irving said on Sunday. "We're not as good as we think we are. That's really what it comes down to. The excitement is done. It's just real basketball now. It's not the potential of the team or where we'll be at the end of the season. It's right now and taking care of what's in front of us."

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