Sooner the better for Marcus Smart

It's probably not a coincidence that the Boston Celtics began their recent playoff surge at the same time that Marcus Smart elevated back to the starting lineup.

Since Smart rejoined the starting group on Feb. 3, the Celtics are 14-7. That .667 winning percentage ranks Boston seventh in the NBA over the past month and a half, trailing only a pack of six playoff-bound teams, including some of the top seeds in each conference.

While he's consistently been a pest on the defensive end, Smart has been quiet at times offensively during Boston's run. He's averaged 10.1 points on 34.8 percent shooting (31.2 percent beyond the 3-point arc) to go along with 5 rebounds, 3.3 assists, and 1.7 steals over 32.3 minutes per game.

Maybe it was being back in the state of Oklahoma, an hour away from where he played his college ball and just a three-hour drive from where he grew up in Flower Mound, Texas, but Smart produced the finest offensive game of his rookie season on Wednesday night against the Thunder.

Smart, the No. 6 pick in June's draft, scored a career-high 25 points on 8-of-14 shooting while connecting on seven 3-pointers. He added nine rebounds, five assists, two steals, and two blocks over 36:32. The only downside: Smart and the Celtics couldn't quite corral Russell Westbrook, particularly during the second half, and the host Thunder emerged with a 122-118 triumph that snapped Boston's five-game winning streak.

Smart shrugged off his big night, telling reporters that he, "definitely felt comfortable out there," but that it was just "one of those nights."

These Celtics, especially while playing without offensive spark plug Isaiah Thomas, need an aggressive Smart on the offensive end. Smart connected on five of the six shots he put up in the second quarter while scoring 14 points that helped Boston carry a four-point lead into the intermission.

Smart finished plus-10 in plus/minus on a night when none of his teammates were in the positive. And he continued to do the little things that have made him so valuable even when he hasn't been a consistent offensive threat.

There was a hustle block on Dion Waiters that prevented an easy layup in transition in the first quarter. Or two instances of heads-up outlet passes that created easy buckets, including a third-quarter sequence in which Smart chased down a long rebound and had the presence of mind to immediately push the ball ahead through traffic to Jae Crowder for an easy dunk.

Smart is still learning how to be a point guard at the NBA level and the Celtics have eased his duties by putting other ball handlers on the court with him, including Evan Turner or, when healthy, Thomas. What Smart lacks now on that end of the court, he makes up for with hustle and grit, particularly on the defensive end.

According to the league's player-tracking data, Smart is limiting opponents to 40.2 percent shooting from the field, or 3.5 percent below their season averages over the 21-game span since he returned to the starting lineup. That's a pronounced drop-off. As Celtics coach Brad Stevens told reporters at Wednesday's shootaround: “He was as ready defensively as any 20-year-old player could be. I would say that’s probably unusual."

Yes, it's easy to forget that Smart just turned 21 earlier this month. He detailed Wednesday how he made the 60-mile trek to Stillwater on Tuesday night to wish the Oklahoma State men's basketball team good luck before it left for its NCAA tournament appearance. Smart hopes the team can extract some revenge on Oregon, the team that upset Smart's squad in the opening round of the tournament during his freshman season.

For Smart, his main focus right now is on trying to get his new team into postseason play as well.

"I’m happy, but there’s still a lot of season left to play," he told reporters Wednesday. "I’m not satisfied right now. This team, we’re doing some things, but we’re still trying to accomplish something [bigger]."

A few more thoughts from Wednesday's loss in Oklahoma City:

• The Celtics shot themselves in the foot throughout Wednesday's loss to the Thunder. Despite being the most sure-handed team in the league recently, Boston turned the ball over 20 times, leading to 26 points. That included 12 first-half turnovers, which prevented Boston from fully capitalizing on shooting 64.1 percent from the field.

Boston also showed a rare lapse in composure late in the third quarter when the Thunder made their run. The Celtics had been up four with a little more than five minutes to play in the third quarter, but found themselves down 12 heading to the final frame.

"We didn’t balance poise and assertiveness well at the level you need to in order to win in this building and in a game they played that well," said Stevens.

The Celtics' defense had been noticeably stout recently, but Oklahoma City's 40-point third-quarter explains the end result. The Thunder also shot 39 free throws -- 22 alone by Westbrook. That helped Oklahoma City put a lot of points on the scoreboard and Boston struggled to keep up as the game slipped away in the second half.

Kelly Olynyk, who has seemed hesitant offensively since returning from an ankle injury, had his best offensive game in a while by scoring 20 points on 7-of-13 shooting over 23 minutes. Olynyk wasn't perfect, but he showed less hesitation with back-to-back 3-pointers during one second-quarter stretch, then went hard at the basket at times later in the game. ... From the opposite end of the spectrum, nothing went right for Phil Pressey. The second-year guard finished with two points on 0-for-6 shooting and had five fouls over 13:24. After being a steadying presence recently, Pressey struggled to get the offense in sync when he was on the court Wednesday and seemed to lose a bit of his own composure when the whistles started going against him.

• The Celtics got some help as both Indiana and Milwaukee lost on Wednesday evening. Miami won and now sits alone in the seventh seed, while Boston currently holds the eighth seed by virtue of the head-to-head tie-breaker over Indiana.