Alley oop. Easy. The renaissance of Kevin Garnett, in the words of Mike Gorman, continues.

It was a 16-point blowout and the Celtics never trailed, but tonight’s 105-89 Celtics win shouldn’t have been so difficult.

The way they were humming in the first quarter, the C’s should have had the Nuggets screaming “Uncle” by halftime. Instead, some starters were still on the court with two minutes remaining. Blame the Celtics bench, and Ty Lawson.

Forgetting a short stint of god-awful defense by Rajon Rondo (you reach, Lawson teach), I have zero complaints about the C’s starters. In fact, the first nine minutes of the game might have been the most complete nine minutes played this season — by any NBA team. Kevin Garnett was leaping around on pogo sticks. The team’s arms were a maze keeping the Nuggets away from the bucket. And oh yeah, the C’s shot a blazing 68.4% from the field for the quarter.

The Celtics did damage inside (Garnett didn’t exactly have a difficult time scoring over — or around — Shelden Williams), and outside (leaving Ray Allen wide open is not a good idea). I know the Nuggets didn’t have Carmelo Anthony tonight, but dealing with the C’s thorough blitz would have been tough for the Nuggets, even if an in-his-prime Michael Jordan had been on their side.

As well as the C’s played in the first quarter (and that quarter was a sliver away from perfect), that’s how bad they were in the second quarter. Defensive principles? Who needs those? Throw them out the window. Ball movement? Not exactly. Before a few reserves scored in garbage time, only Glen Davis and Semih Erden scored off the bench. Speaking of Davis, was he high during his halftime interview? Drunk? Just winded? If I didn’t know any better, while Davis slurred his way through the interview, I would have sworn he was on some serious drugs.

For one night, Ty Lawson was the bane of my existence. Is it THAT easy to waltz right by Nate Robinson? Is Rondo THAT hurt, where Lawson can make him look like he’s walking in quicksand? With his speed and aggression, Lawson turned this game around and kept it close. He also came *this close* to causing me to break my hand, as I almost punched a whole through the wall when he repeatedly burned the Celtics point guards.

Contrary to what we saw tonight, Lawson isn’t really the league’s best point guard. He’s pretty good, I’ll give him that, and absurdly fast, but the Celtics second-quarter defense (or lack thereof) helped him look like an evolutionary mix of Carl Lewis, Usain Bolt and Tony Parker. In the second half, Rondo stopped gambling and played straight-up defense, and the big men started to provide help in pick-and-roll situations. Suddenly, the game didn’t look so easy for Lawson. That’s what happens when you remember (and actually use) your defensive principles.

To be fair to Rondo’s defense, Chauncey Billups needed 10 shots to score five points. If Rondo felt any resentment toward Billups for whatever happened this summer on Team USA, well, count one for Rondo. He made his point. At least for tonight, Billups didn’t deserve to be on the same court as the Celtics’ star.

Did anything else happen?

Rondo briefly left the game, and could be seen stretching on the sideline. It was unclear whether his hamstring or feet were bothering him. Marquis Daniels also looked to injure himself — the right thumb. If you recall, he injured his left thumb last season.

My brother came up with the best description of the starting Celtics frontcourt I’ve heard yet: “Get mentally abused by one big man, and physically abused by the other.”

J.R. Smith is, for lack of a better word, interesting. In his return to the Garden, Shelden Williams didn’t exactly receive a loving reception. It was more indifferent.

With less than a minute left, Von Wafer took an obscene 30-footer with plenty of time left on the shot clock.

Glen Davis and Nene had some beef. Sadly for Davis, the beef was not food.

And, umm, did you see Erden’s finger roll? If Erden had become black, worn short shorts, been the best scorer in the league, and looked like a skinnier version of an ambidextrous person, he could have briefly convinced people he was George Gervin.

Oh, I forgot one thing: It’s a shame Avery Bradley doesn’t have a grasp of the Celtics’ offense yet. His defense is scintillating. I’m normally the type of person who only notices defense if it’s bad. (Like when Robinson and Rondo were repeatedly roasted by Lawson.) But Bradley, as KG does, forces you to admire his defense, by being THAT much more impressive than everyone else. Unfortunately, the rookie still hasn’t learned how to contribute with the ball in his hands. Once he does, his defense will be a weapon.

Tonight’s game should have been less competitive, but the Celtics accomplished what they needed to. They sent George Karl home still searching for his 1,000th win. And if you just closed your eyes when the bench was in, the Celtics won in very impressive fashion.

*****

P.S. — Garnett scooted over to George Karl after the game. My imagination might be running wild, but I bet he was clearing things up after his alleged “cancer patient” comments. Karl, who fought cancer all of last season and still isn’t completely out of danger, took offense to Garnett’s alleged comments.