MIAMI - Lou Williams and Doug Collins were lounging on the pricey sideline seats of AmericanAirlines Arena.

The 76ers' off-day practice in Miami had just ended and Collins walked over to join his combination guard, the player he has said is "the voice" of this team.

You could have imagined any number of conversation topics between player and coach: How was Lou's hamstring feeling? Should they approach Monday's game any differently in terms of minutes played or plays designed for Williams? Is he seeing anything specific out on the floor?

But what were they actually talking about?

Collins paraphrased: "I said, 'Lou, how'd you think today went, our preparation, our film session?' I said, 'Is there anything more I can be doing to help our team?' "

Yes, that's right, Collins was asking Williams for the team's perspective on Collins' first-game coaching performance: On Saturday afternoon, the Sixers lost the opening game of their best-of-seven series against the Miami Heat, 97-89.

The second game of the first-round series will be played Monday night.

And since adjustments are paramount in the NBA playoffs, Collins was searching for feedback, not just on the on-court X's and O's, but also on his substitutions and game-planning.

Collins trusts Williams and - going forward against the superiorly talented Heat - he's going to need Williams in midseason form, not coming-back-from-injury form.

Saturday's loss was Williams' first game in more than two weeks, and it was also his first time playing five-on-five since straining his right hamstring against the Milwaukee Bucks in early April. Williams finished the game 3 for 10 from the floor with 10 points. He looked rusty early, very much like a guy who hasn't had much court time lately, but he looked more fluid later, which is how he'll need to look as this series progresses.

"I liked what I saw from Lou," said Sixers power forward Elton Brand. "First time he got in, he missed a few shots, but after that he got his rhythm, hit some big threes for us, got some steals. I think he's going to be better next game."

Williams said that during Sunday's practice, he was "dealing with a lot of soreness." The injury, which happened when Williams rose for a jumper, could reoccur at any moment, a fact Williams says remains in the back of his mind.

"I just don't want to pull it again," Williams said. "Any time you're dealing with something like a hamstring, if it goes again, I'm done."

The good news for the Sixers is that Williams said his outside shot felt good, despite those early misses, and that going forward he'll attempt to get to the rim more, even though jumping is the most difficult movement with this type of injury.

"First game, I was able to get out there and kind of feel my way out," Williams said. "And in the second game, I probably won't be as tentative."

The Sixers desperately need the Williams of old because, as evidenced during Saturday's anemic second quarter, their second unit depends on his aggressive scoring.

"That's what I do, that's my impact on this team . . . to score the basketball," Williams said. "I know I'm better than 10 points."

Contact staff writer Kate Fagan at kfagan@phillynews.com. Follow her on Twitter at twitter.com/DeepSixer3 and read her blog, Deep Sixer, on Philly.com