Sitting inside the visitor's locker room before Wednesday night's tip-off against the Los Angeles Lakers, Terrence Williams was watching game video with one of the Celtics' assistants.

Williams will indeed do all he can to get up to speed as quickly as possible, well aware that he has a small window of time -- 10 days to be exact -- to prove he's an asset worth keeping around.

The former lottery pick drafted by New Jersey (now Brooklyn) had two points and two assists along with two rebounds in Boston's 113-99 loss to the Los Angeles Lakers.

"He was good," Rivers said. "You can see some of the things . . . he's a great ball-mover."

Which is exactly what a team like the Celtics need with their floor general Rajon Rondo out for the rest of the season.

While Rivers sees tremendous potential in Williams to be an elite defender, his game offensively needs work, too.

"I thought he was really tentative at times, coming off of picks," Rivers said. "But again, you got those guys on the floor. You kind of just want to fit in."

Having not played in an NBA game in nearly two years, it's going to take Williams some time to get used to the speed of the game, which tends to catch most people off balance.

It's too soon to say how well Williams will fit in, but it's clear that he's most likely going to get opportunities in the near future to play if he continues to play defense the way he did against the Lakers.