Anxious moments down stretch will help in long run

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Al Horford was impressive in his first game with the Celtics, making solid contributions at both ends of the court.Maddie Meyer

It wasn't a storybook finish for the Celtics, and that's a good thing. They needed to struggle a little after coasting to a 23-point lead with 7:36 remaining against the patchwork Brooklyn Nets.

An easy victory would have continued the wave of momentum from the preseason, when the team looked flawless at times. But that's not NBA reality. The Celtics have their weaknesses. And they are going to face teams that play hard regardless of the score, as the Nets did down the stretch in this game.

The Nets are eerily reminiscent of the 2013-14 Celtics, who played hard throughout the season, though it only resulted in 25 wins. The Celtics are no longer the ones doing the chasing. They are going to be chased.

They have a chance to win every game, a first in the Brad Stevens era, and Wednesday's 122-117 victory in front of sold-out TD Garden provided the type of discomfort they needed.

Privately, Stevens probably grinned on the flight to Chicago — where the Celtics play the Bulls Thursday in the home debut of Chicago native Dwyane Wade — because his team now understands it must commit 48 minutes to defense.

The Celtics cannot rely on an elite starting lineup. Despite the absence of Marcus Smart, the bench has to be better, especially when playing against the Nets' reserves. It's funny, new Brooklyn coach Kenny Atkinson allowed his reserves, including rookie second-round pick Isaiah Whitehead and second-year player Chris McCullough, to play key minutes during the Nets' furious late-game run, obviously trying to get his young guys some tight-game experience.

What if the coach had gone to his starters earlier? The outcome may have been different. Stevens was forced to put in his starters back in with 2:07 left and with an 8-point lead, and they proceeded to allow it to be reduced to 3 with the Nets getting two clean looks at 3-pointers in the final 20.9 seconds.

"It was 110-87 and we started shooting bad shots and not guarding and throwing it to the other team," Stevens said. "It's how quickly it can change; we all know that. I was hopeful not to have to put those guys back in but I probably went a little longer than I normally would have, not doing that. So we've got to play better in that moment."

Meanwhile, the second half of the fourth quarter allows Stevens some teaching points because the preseason went perhaps smoother than he expected. And for the first 3½ quarters, the Celtics looked exactly like the team projected to push the Cavaliers in the Eastern Conference.

They still are. The roster is deep and talented. The presence of Al Horford — 11 points, 5 rebounds, 6 assists, 4 blocked shots in 27 minutes — made a positive impact on the defense and he blended well into the offense. Stevens is still experimenting with playing rotations but overall it was a solid effort that was tainted a bit by the final six minutes.

A win is a win. It's the NBA and every team is capable of a rally, but the Celtics have to be harder on themselves than years last. They have to expect elite performances if they expect to be an elite team.

"We want to be great, we want to be one of the top teams in the NBA, and that can't happen," Isaiah Thomas said. "There's no excuse for it. If we want to be a top team like they say we're going to be, we have to do a better job of closing games out."

So there is definitely plenty to chew on before Thursday's nationally televised games with the Bulls. Small forward Jae Crowder wasn't exactly thrilled the Celtics were one of two teams (along with the Sacramento Kings) to begin the season with a back-to-back set.

But this is really what they wanted. They are playing on Thursday because they are considered one of the league's better teams. The matchup with the Bulls is considered a showdown. The NBA community wants to see the Celtics with Horford and his motivated teammates after they were disposed of by the Hawks in the first round of the playoffs last season.

The Celtics will be taken seriously by their opponents each game. There are going to be more stressful nights, more back-to-backs, and more nationally televised games after a tough home game. The Celtics better get ready for the pressure. The bench better be ready to hold large leads to give the starters an early night.

Boston's season debut wasn't as sparkling as it could have been, but it will eventually be a positive experience for the future. It's hard to boast over a 5-point win against a team expected to win 20 games. It should make these guys hungrier to play a more complete game.

In Game 1, Stevens wanted to see how his team reacted to late-game adversity. The Celtics passed the test — barely. It's time to move on.

"I thought that it would be, obviously, a great opportunity to play the right way and figure out a way to keep them at bay as they come hard-charging," Stevens said. "It's hard to play with a team that's got nothing to lose, that's flying at you and everything else. Wasn't to be. Probably will be . . . less, less likely to leave [the reserves] in that long if we're in a similar scenario. Hopefully we learn from it and we're not in a similar situation."