WALTHAM, Mass. -- Boston Celtics coach Brad Stevens has always been measured with his praise of players, especially in the early stages of training camp, when it would be easy to overhype his charges.

Which is why it was notable that Stevens offered such high praise for point guard Isaiah Thomas before Thursday's practice session at the team's training center.

"Isaiah is last on our team in field goal attempts through the four days of practice that we’ve statted. And [he] has completely been unbelievable on offense, which tells you all that he’s doing for everybody else," said Stevens. "He’s playing very unselfish. He’s making the right read, regardless of situation, and he’s not forcing anything. He really played great point guard on offense the whole time."

That Thomas is spearheading Boston's offensive attack should come as no surprise. The Celtics owned an offensive rating of 109.2 points per 100 possessions -- the best mark on the team -- when Thomas was on the court after his late-February arrival last season. Boston's rating dipped more than nine points per 100 possessions without him on the court in that span.

But Thomas is typically regarded as a scorer after averaging 19 points in 26 minutes per game over 21 regular-season appearances for the Celtics. What's often overshadowed is that he averaged more assists per 36 minutes (7.5) than at any other point in his career, once again hammering home his impact on Boston's offense as a whole when he was on the court.

Stevens said he has never asked Thomas to put more of a focus on creating, but that he has simply stressed the importance of read-and-react basketball to all of his players.

"The thing that I’ve asked out of him is the same that you’d ask about anybody -- if there’s a basketball play that’s happening, the game is going to tell you what to do and you’ve got to make the reads," said Stevens. "We spent a lot more time, even in our first four practices, on reading and reacting off of each other -- more of in a constant-movement, somewhat-random-yet-organized manner, so you know where people are going to be, but it’s not going to be exact time and again. And you just have to make basketball reads. Sometimes they are going to be backed up off of [Thomas], and he’s going to be able to score; sometimes he’s going to be able to blow by them and get to the rim and make shots; sometimes he’s going to have to make the right read for the other guy.

"What happened the other night [during Boston's scrimmages at the team's open practice] was, [Thomas] got a couple of his shots in transition, but he started the game by finding spaces because everybody was pulled in; [Thomas' team] ended the game by Amir Johnson laying the ball in, because everybody was extended out because the spacers had already made shots. That’s kinda the way the team works and his task will be continuing to make the right reads."

The Celtics operated that scrimmage with Thomas starting alongside Jae Crowder, Jonas Jerebko, Kelly Olynyk and Johnson. That's a combination that features two of Boston's most versatile defenders, both capable of spacing the floor with their 3-point shooting; a big that likewise stretches the floor; and the team's best pick-and-roll guy. Stevens has stressed that he won't over-complicate the offense when Thomas is on the court because of his ability to make the right plays in simple spread pick-and-roll sets.

Even still, Thomas has expressed a desire to diversify his offensive arsenal this season and said he spent much of the offseason watching film of Steve Nash.

"I got a lot of one-foot shots that I’ve been working on, which extends to the 3-point line," said Thomas, who was working on one-footed foul-line floaters before practice Tuesday. "And I know the first time I do it, [reporters] are going to be like, ‘What the hell is he doing?’ But I definitely worked on it. I’ve been working on that all summer. I ‘ve just been trying to figure out ways to continue to get better and continue to be the best player I can possibly be."

The biggest challenge for Thomas and the Celtics is figuring out how to maintain their offensive output when teams put an intense focus on Thomas, much like the Cleveland Cavaliers did during last year's first-round sweep (Thomas averaged 17.5 points per game in elevated minutes, but shot just 33.3 percent from the field and 16.7 percent from beyond the 3-point line).

Crowder, who paired often with Thomas as part of Boston's dominant second unit last season, acknowledged a need to find other ways to generate points when teams take away the pick-and-roll game.

"We came to a point last year where Cleveland took away his pick-and-roll and trapped him every time. So it made us adjust," said Crowder. "I’ve talked to him about it and our way of adjusting is him trying to find other guys and trying to make a play for him -- not necessarily [Thomas] making a play for us each and every time."

Added Crowder: "We’re just trying to adjust because, when we got to the playoffs, they adjusted to him and adjusted to what he brought to our team, and that’s him playing off pick-and-rolls. When they tried to take that away from him, we’re trying not to be just one-dimensional at that point."

Much of the preseason focus on Thomas has revolved around whether he might elevate to a starting role this season -- a question that invariably pops up in any interview he conducts. Stevens has stressed that his focus is more on finding pairings that work best together and he'll worry about how to get everybody minutes from there. For his part, Thomas has repeated often that, "As long as I’m out there playing and getting the minutes that I deserve, I’m all for [any role]. I’m all for the team and whatever it takes to win. That’s an honest answer; that’s real."

There are lingering concerns about how Thomas would fare, defensively, as a starter as his size can create matchup troubles (though, his defensive rating last season was 101.9 when he was on the court and a versatile cast around him helped limit his troubles).

What's obvious from last season and becoming clearer with Stevens' comments Tuesday is that Thomas is the straw that stirs the drink. He was Boston's final player introduced at Tuesday's scrimmage -- the sort of spot typically reserved for a team's best player.

Regardless of how he's utilized, it's obvious that Thomas is going to spend a lot of time on the floor this season. And the Celtics are certain he'll make those around him better when he is.