The Boston Celtics beat the Oklahoma City Thunder 134-129 on Sunday at TD Garden in a showdown between two teams that have recently hit their strides.

Boston improved to 9-1 in its last 10 games with its fourth win in a row, while Oklahoma City saw its own seven-game winning streak come to an end.

Kyrie Irving led the way for the Celtics with 30 points, 11 assists and four rebounds on 14-of-19 shooting from the field. Marcus Morris (19 points and seven boards) and Al Horford (17 points and nine rebounds) were two of the eight Celtics to finish in double figures.

Paul George spearheaded the effort for the Thunder with 37 points, while Russell Westbrook notched a sixth straight triple-double with 22 points, 16 assists and 12 rebounds. Despite Westbrook's impressive statistics, his critical turnover with OKC facing a two-point deficit in the final 10 seconds was the most important play of the game.

Despite Drama, Kyrie Still Best Bet to Lead Celtics to Finals

Boston is in the middle of a winning stretch, but many of the headlines have come off the court with Irving's future drawing attention with a 2019-20 player option looming.

Tim Bontemps of ESPN.com summarized the situation, noting the five-time All-Star said he was going to re-sign with the Celtics when asked about it this past offseason but recently quipped, "Ask me July 1," when discussing it again.

Bontemps also noted some of the team's young players have "been frustrated with Irving" after he "repeatedly aired his grievances" about them through the media and criticized head coach Brad Stevens for not drawing up a play for him at the end of a loss to the Orlando Magic.

There may be some frustration in place, but Irving demonstrated why he is still the best bet to lead the Celtics to the NBA Finals during Sunday's matchup with OKC. He poured in 20 points on 9-of-12 shooting in the first half alone, impressing with his brilliant ball-handling and gliding through the defense with behind-the-back moves and an explosive first step.

Thunder defenders struggled to stay in front of him, underscoring the looks he opens up for the talented depth surrounding him with the defensive attention he draws every night with his slashing and perimeter shooting.

Boston made Game 7 of the Eastern Conference Finals last season while Irving was sidelined, but it didn't have that one playmaker who could get his shot whenever he wanted in crunch time and go toe-to-toe with LeBron James. The Cleveland Cavaliers held the Celtics to just 79 points in Game 7 as a result, clinching a fourth straight trip to the Finals.

Irving was part of three of those Finals runs and has one of the biggest shots in NBA history on his resume with his winning step-back three in Game 7 of the 2016 series against the Golden State Warriors.

That type of clutch playmaking was missing for Boston in last year's run but will be present alongside a defense that is second in the league in defensive rating, per NBA.com.

With that defense taking some of the pressure off the offense and Irving leading the way as a playmaker who can find his own looks and create shots for his talented teammates, the Celtics have the roadmap to the NBA Finals in place.

PG's Ascension Makes OKC a Viable Threat for 1st Time Since KD's Exit

The Thunder made four Western Conference Finals and one NBA Finals during Kevin Durant's nine seasons with the franchise, establishing themselves as regular title contenders with him and Westbrook leading the way.

The Thunder have lost in the first round of the playoffs both years since Durant left following the 2016-17 season. Westbrook didn't have enough help in the first year as a triple-double machine who could only do so much, and there was an awkward fit with George and Carmelo Anthony playing together last season.

Anthony is no longer there, but George has emerged as the team's go-to scorer who appears far more comfortable in his role.

Entering play, he was averaging 27.6 points, 8.0 rebounds and 4.0 assists a night while shooting 41 percent from three-point range. The scoring, rebounding and three-point percentage are all career highs, and he provided a silver lining in the loss and continued his brilliant play Sunday with more than 30 points for the seventh time in eight games.

While George was an All-Star player named to All-Defensive teams during his time with the Indiana Pacers, he has never played at this level. His ascension has been even more important with Westbrook struggling in some aspects with a 24.9 percent shooting clip from deep and 64.5 percent mark from the free-throw line.

Past post-Durant Thunder teams would have been lost with Westbrook forcing shots and struggling from the field when compared to the best the Western Conference has to offer, but they have an elite two-way threat to carry the load in 2018-19.

OKC is the No. 3 seed in the West thanks largely thanks to George's ability to score with shooting and slashing as a matchup nightmare at 6'9". He can also defend the opponent's best player come playoff time as a three-time All-Defensive selection.

Westbrook no longer has to do everything, and the Thunder have the talent with two All-Stars and solid role players in Steven Adams and Dennis Schroder to match up with anyone but the Warriors in the postseason.

What's Next?

Both teams are in action Tuesday with the Celtics at the Cleveland Cavaliers and the Thunder hosting the Orlando Magic.