LAS VEGAS – Semi Ojeleye is aware that most of the time when he’s on the floor, there’s likely to be at least two or three players who shoot the ball better than he does.

But that doesn’t mean he can’t at least be an offensive threat, which has been a focus of his throughout most of Summer League play.

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Ojeleye acknowledged that improving his shooting mechanics has indeed been at the top of his need-to-improve list.

And while the three Summer League games Boston (2-1) has played are indeed a small sample size, it’s clear that Ojeleye is showing clear signs of being a better player offensively now than he was this past season.

In Boston's three Summer League games, Ojeleye has averaged 10.7 points while shooting 43 percent from the field along with 3.7 rebounds and 3.0 assists.

“I’m just trying to be more of a threat on offense,” Ojeleye told NBC Sports Boston. “I realize that’s one thing I can do to take a step forward going into next season. Just attacking more, making good decisions.”

Even when he’s not scoring, Ojeleye wants to at least be considered a threat.

One of the first things he has done has been to work on improving his mechanics.

Prior to Summer League, Ojeleye said he spent time working with Los Angeles-based NBA basketball skills coach Drew Hanlen, who has worked on improving the shooting of some of the league’s top players.

Among his lengthy list of NBA clients are Washington’s Bradley Beal, Philadelphia’s Joel Embiid, Zach LaVine of the Chicago Bulls and Cleveland’s Jordan Clarkson.

Ojeleye's biggest problem last season was that he shot the ball rather flat, so getting more lift on his shot has been a point of emphasis.

In addition to working with Hanlen (something Ojeleye said he did before Summer League and will reunite with Hanlen afterwards), Ojeleye said he has also spent time working with Celtics assistant coach Scott Morrison.

Morrison said a key emphasis when it comes to Ojeleye’s improved shooting has been him making sure he gets his elbow under the ball more.

“He’s better, but he needs to keep working on it,” Morrison said. “I was happy with his shooting when he came back (for Summer League).”

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In addition to better mechanics on his shot, Ojeleye has also looked to beat players off the dribble more and finish at the rim.

“He’s trying to push himself, do some things that he didn’t necessarily do in the regular season,” Morrison said. “Doing more stuff out of pick and rolls and making reads off his drive is something he’s worked on.”

And that work, Ojeleye believes, will pay off in having an even better season than he had as a rookie.

“It’s all about staying ready,” he said. “All season, you never really knew when your opportunity would come but you still had to stay ready, and that’s what I tried to do. I try to approach every day to get better, do what I have to do from sun-up to sun-down to be better. So, when the opportunity came (last season) I tried to maximize it. Same thing this offseason; just try to maximize opportunities from sun-up to sun-down.”

BOSTON -- Terry Rozier will become the latest player drafted by the Boston Celtics to not get a contract extension agreed upon prior to the start of his fourth NBA season.

The decision by Rozier to not accept the offer worth about $12 million annually was strictly business, with no hard feelings or bitterness on Rozier’s part towards Boston or vice versa.

With restricted free agency on the horizon, Rozier’s focus now is all about basketball.

“I’m in a great situation,” Rozier, smiling, told NBC Sports Boston. “My team felt it wasn’t good for me to sign an extension right now. It opens my options a little bit, but I’m focused on what’s happening right now.”

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And that’s preparing for the season opener against Philadelphia on Tuesday, one of the few teams expected to seriously challenge Boston for supremacy in the East this season.

Rozier had a breakout performance in the playoffs last season which included strong play in Boston’s second-round series knockout of the Sixers in just five games which at least one Celtics player felt was one game too many.

"We should have swept them but we let them win one game,” Jayson Tatum told reporters on Sunday afternoon prior to the Celtics practice.

One of the reasons why Boston was so successful in the series was the play of Rozier.

Against Philly in the playoffs, Rozier averaged 19.0 points, 7.2 rebounds and 4.4 assists while shooting 41.5 percent from 3-point range.

Rozier’s play in that series, and the playoffs in general, established him as a player with starter potential in this league.

Which is why, despite his restricted free agent status, there are a number of teams that are expected to make a run at him. That's due to Boston having five-time All-Star Kyrie Irving, who will be an unrestricted free agent this summer but recently went public with his desire to re-sign with the Celtics sometime in July.

Coming into this season, Rozier hadn’t spent much time thinking about his contract situation.

Instead, he has been focused on doing whatever he can to better himself as a player with the knowledge that his minutes and those of several Celtics, will probably take a dip from where they were a year ago.

 “I feel like I’m one of those guys, I can make it work, whether it’s a little bit of space, a little bit of time,” Rozier said. “I’ve always been a team guy. For me, to be that way it has always opened up stuff for me, with me being about the team. I think it’ll all work out for me.”

And just like he tries to push Irving in practice daily, he knows in doing so will also help him in terms of playing time.

“I’m gonna keep putting that pressure on Brad (Stevens) to play me,” grinned Rozier who added, “and just have fun with it.”

BOSTON — Jayson Tatum often reminded Joel Embiid this summer about how his Boston Celtics eliminated the Philadelphia 76ers in five games during an Eastern Conference semifinal series. With the two teams set to meet again on opening night on Tuesday, the trash talk should start fresh for two teams that are budding rivals.

Tatum was asked about working out with Embiid over the summer and — as was spotlighted in the videos that emerged from those sessions — Boston’s second-year forward takes every opportunity to remind Embiid of the Celtics’ playoff dominance.

"I just kept reminding him that we almost swept them,” said Tatum. "We should have swept them but we let them win one game.”

While Tatum said the trash-talk was all playful, it’s clear the Celtics and 76ers are primed to be long-time rivals given their shared status as two of the East’s best young teams.

After playing a whopping 11 times last season — two preseason, four regular season, five postseason games — these two teams won’t need much of a reintroduction.

"Definitely some animosity,” said Tatum. "We won, so they are probably a little more fired up or angry than we are, but we're excited to play. We had a lot of good matchups with them last year, a lot of great battles, especially in the playoffs.”

Celtics coach Brad Stevens spoke highly of his team’s opening-night opponent.

"You watch them all summer — I think they’re one of the most creative teams on offense and defense in the league,” said Stevens. "I greatly appreciate watching them as a basketball fan, let alone having a responsibility to prepare for them. So, yes, I enjoy watching them play. I think [coach] Brett [Brown] does a great job and obviously they’re phenomenal.”

While Stevens showered Philly with praise, Celtics guard Terry Rozier is excited for the trash-talk and hard-nosed play that undoubtedly awaits, particularly with Embiid on the other side of the court.

"It’s gonna be two teams getting after it, whether it’s biting, scratching, no matter what you have to do to win, that’s what it’s gonna be,” said Rozier. "I think we’re looking forward to it. I know I am. I like the stuff that Embiid talks. It’s good for basketball. It’ll get you hyped up, so you know, if they like it, we love it. It’s going to be a lot of fun. We ready for it.”

Tatum wouldn’t take the bait when asked whether the Celtics are currently ahead of the Sixers, especially given how Boston is adding a pair of All-Stars in Kyrie Irving and Gordon Hayward to a team that won in five games during the playoffs.

Tatum noted how the Celtics can’t lean on what they did last season. Added Tatum: “It’s going to take some time for us to look as well as we did in the playoffs … we’re not going to be perfect.”

For his part, a sleepy Irving, who apologized to reporters for being tired and short with his responses before Sunday’s early afternoon practice, didn’t have much thoughts on the Sixers.

“I don’t know. All I know is destroy,” said Irving. "That’s all I know. So once we go out there that’s the only thing.”