Celtics reach 50-win milestone, already focused on No. 51

NEW YORK -- With an orange towel draped around his neck and a blue heating pad protruding from his game shorts, Isaiah Thomas kept stomping on the court in celebration each time a teammate made a big play in the fourth quarter of Sunday's victory over the New York Knicks. He did it for Terry Rozier's probing and-1 layup and again when Marcus Smart elevated for a rare alley-oop slam courtesy of a floating Rozier feed.

There haven't been many breezy nights like this for Thomas. For all the success the Celtics have had since his arrival in February 2014, Boston routinely has had to grind out wins. Sunday was a rare opportunity for Thomas to quite literally kick off his high-tops and simply savor the final frame of a 110-94 triumph at Madison Square Garden.

That it was the 50th victory of the season for the Celtics made it just a little bit sweeter. When Thomas first arrived in Boston via trade from Phoenix, the Celtics were 11 games under .500 and had an uncertain future. Despite clearly trending toward the lottery, the Celtics liked the off-the-bench punch that Thomas could provide and were willing to sacrifice a few pingpong balls if he could aid their quest to return to contender status further down the road.

The Celtics won 40 games that year as part of a furious late-season surge and sneaked into the playoffs. Thomas elevated to All-Star status a year later when Boston won 48 games. And now the 5-foot-9 spark plug has muscled his way into the MVP conversation, an elite offensive player for a Boston team that won the race to 50 wins in the Eastern Conference this season.

"It’s nice. I’ve never won 50 games in my whole career," Thomas said. "It was definitely an individual goal of mine coming into the season, to win 50 games. I’m just glad we got to that, but, like I keep saying, we still got a lot more work to do."

These Celtics, relentlessly motivated to continue building, are now guaranteed to be no worse than tied with the Cleveland Cavaliers heading into what might be a showdown for the No. 1 seed on Wednesday night at TD Garden.

Thomas and his teammates are unlikely to linger on reaching the 50-win milestone beyond Sunday. When peppered with questions about the looming matchup with the Cavaliers, these Celtics immediately reverted to all-business mode.

But even Celtics coach Brad Stevens, forever locked on the growth mindset, seemed to take a fleeting moment to savor the half-century mark, especially considering how his team has evolved in his four seasons.

"I think that, a couple of years ago, I would have thought that [getting to 50 wins] was going to be something that we were really going to have to build for a while to [achieve]," Stevens said. "Obviously, we've been lucky to strike on a couple of guys. Everybody's got a like mind with regard to the bigger purpose of playing for the Celtics and trying to compete every night.

"So we're happy, but we've got to finish out these next five games well and then get ready for the playoffs. We'll look at whatever we accomplish at the end of the season at the end of the season."

It was this Knicks franchise that essentially ushered in the Stevens regime, ending Boston's most recent Big Three era with a first-round dispatch of the Celtics during the 2013 playoffs. Boston hit the detonator in the months that followed, trading away Paul Pierce and Kevin Garnett to New York's other basketball squad and collecting the assets that should help the Celtics remain a contender deep into the future. Doc Rivers bolted for Hollywood and Stevens was the surprise choice to rebuild the franchise.

Now, the future isn't so rosy for the directionless Knicks. Boston built as much as a 27-point lead and never trailed during Sunday's game. Celtics players and coaches were peppered with questions by the New York media about how Boston was able to reverse its fortunes so quickly.

Sunday's victory produced the 32nd 50-win season in Boston's franchise history, tying the Celtics with the Lakers for the most such seasons in NBA history. The Lakers haven't won that many games since 2011 and, like the Knicks, it's unclear when they can get back to contender status.

The Celtics? Well, they're here. A victory Wednesday and the Celtics will position themselves to secure the top spot in the Eastern Conference. How in the world did they make this happen so quickly?

"Together. We’re doing it together. We do everything together," Crowder said. "We work together, we take losses together and we learn together. As we grow, we do everything together. And with additional pieces like Al [Horford], it’s really helped us just with our basketball IQ on the court. We have a lot of good players, but we play smarter; we do a lot of good things on the basketball court on both ends. But we’ve done it together to get to this point."

Horford jumped on this ride on the upswing, signing a max contract last summer, but Boston's rise was part of what made the Celtics so intriguing to him.

"It’s a credit to Coach and it’s a credit to the guys in the locker room," Horford said. "We have a lot of young guys and I feel like they’ve all grown up really quickly and obviously, needless to say, Isaiah’s game rising to another level also helps. I just feel like our guys really get it and I’m just very happy to be a part of it."

Echoed Smart: "It just shows the type of coach that Brad is and the coaching staff we have. They put in the time and work to make sure that we can be in the right spots and have the chance to win every game. For this team, everybody doubted us, that we were in the rebuilding stage. For us to come out and do the things we’re doing early in the process for us feels good. I know fans love it, Boston loves it, and this team has really prided themselves on it."

Stevens was asked earlier this week about Boston taking over the top spot in the Eastern Conference. He noted how, examining the 17 championship banners that decorate the walls inside the team's practice facility, there are no celebrations for this organization for what it has accomplished 70-something games into the season.

And by the time the Celtics' plane landed back in Boston, the focus had undoubtedly shifted from Boston's 50 wins to how they get No. 51 against the Cavaliers.

"It’s the next game, so it’s definitely the most important one," Thomas said. "We’ll be ready."