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On Nov. 8, the Suns coughed up a 22-point second-half lead and suffered a disheartening loss on their home floor against the Celtics. On Wednesday morning, before these teams met again at TD Garden, Suns coach Igor Kokoskov brought up that massive collapse to his team. He wanted them to remember it, and he wanted to be sure that if a similar situation arose, his team would not crumble.
“We couldn’t close that game,” Kokoskov said. “Tonight, we played with discipline, we played unselfishly, we found open people and some guys made big plays in crunch time.”
This time, Phoenix’s lead swelled to as many as 13 points in the fourth quarter. And there were moments when it appeared the Suns would be too scattered to sustain it, but they steadied themselves in time to hand the Celtics one of their worst losses of this season, 111-103.
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Good vibes can fade suddenly, and for the Celtics an eight-game winning streak has now been followed up by consecutive losses, including this one at home against the team with the worst record in the Western Conference.
The Celtics entered the night without starters Al Horford and Marcus Morris, who both sat due to knee soreness. And just over two minutes into the first quarter they suffered another loss, when Aron Baynes broke a bone in his left ring finger when his hand was tangled with Suns rookie Deandre Ayton’s hand.
According to a league source, Baynes will require surgery and will likely be sidelined for at least one month. Coach Brad Stevens said after the game that the break was so obvious that even he could identify it on the X-ray.
Rookie big man Robert Williams played well in place of Baynes, going 4 for 4 and finishing with 8 points, 8 rebounds, and 5 blocks. And he will probably continue to get opportunities while Baynes is out. But on Wednesday he was outdueled by his fellow rookie Ayton, the No. 1 overall pick of last June’s draft, who tallied 23 points and a career-high 18 rebounds.
The Suns pummeled the undermanned Celtics on the backboards throughout the night. Phoenix grabbed 21 offensive rebounds, the most by a Celtics opponent since the Knicks also had 21 on Nov. 11, 2016. The Suns held a 56-37 rebounding edge overall.
“It breaks people’s spirit,” Celtics point guard Kyrie Irving said, “getting offensive rebounds and getting new possessions and converting off that.”
Irving led the Celtics with 29 points and 10 assists. The Celtics had a near-perfect first quarter, making 17 of 24 shots, but they made just 21 of 61 the rest of the game. The Suns outscored the Celtics in the second, third, and fourth quarters.
As the Celtics tried to engineer a comeback, it became clear they simply did not have the juice on this night. Passes that were so precise during their winning streak were suddenly bouncing off of bodies or missed all together.
“You know, even our passes that were caught weren’t delivered on target,” Stevens said. “But I thought that [the Suns’] quickness and athleticism affected us in some ways, and then I thought we got sloppy at times.”
This game ended the most cushy part of Boston’s schedule this season. Of Boston’s last 15 opponents, the Mavericks were the only ones that entered Wednesday with a winning record. On Friday, Giannis Antetokounmpo and the Bucks come to Boston, and similar challenges will arise frequently over the next month. The hope is that Horford and Morris will return soon.
The players did not necessarily seem alarmed after Wednesday’s setback, but they made it clear there are still plenty of areas to fine-tune, including effort.
“It’s like for some games that we’ve played, when we try, we’re in the game all the time,” Irving said. “And when we don’t, we’re clearly not. We [can’t] look to the refs or anything like that. For us as a growing team and learning from one another, we have to continue to build that cohesion.”
The Celtics led by as many as 6 points in the third quarter but the Suns took the lead with an 18-7 run and never relinquished it.
Near the start of the fourth quarter the Celtics committed turnovers on three consecutive possessions, and the groans in the crowd increased after each one. The Suns drilled three 3-pointers in the opening four minutes and took their largest lead, 97-84, on a Kelly Oubre 3-pointer with 8:18 left.
Much like the last time these teams met, Phoenix appeared to be trying to run the clock out rather than sticking with what was working, and it was not effective, as the Suns scored just 4 points over a six-minute stretch.
Terry Rozier started Boston’s comeback by hitting back-to-back 3-pointers, and Devin Booker helped the cause by fouling Marcus Smart on a deep 3-pointer with the shot clock running down.
The Celtics pulled within 103-98 on a Smart 3-pointer with 1:49 left, but Smart then gave those points back at the other end, when he fouled T.J. Warren on a 3-pointer. After Irving hit a 3-pointer to make it a 5-point game again, Oubre answered with another 3-pointer for Phoenix, essentially finishing off Boston with 49 seconds left.
“We’ve got to just play hard the entire game,” Tatum said. “We can’t pick and choose.”
Adam Himmelsbach can be reached at email@example.com. Follow him on Twitter @adamhimmelsbach.