It doesn't happen often, but Patriots coach Bill Belichick got a taste of his own medicine on Saturday, and it came during a pivotal point during New England's shocking 20-13 loss to Tennessee.

During the fourth quarter of the game, Titans coach Mike Vrabel exploited a loophole in the NFL rulebook that allowed Tennessee to run one minute and 49 seconds off the clock without running a single play, and it was fitting, because it was the same strategy that Belichick used during a 33-0 win over the Jets in October.

In Saturday's game, the Titans had a fourth-and-5 from the Patriots' 36-yard line with just 6:33 left to play. Due to the weather, Vrabel didn't want to kick a field goal, so he decided to punt the ball, but not until after his team took a delay of game penalty, which took the clock down to 5:52. Following that penalty, the Titans got a fresh 25-second play clock, and they let the new clock tick down to zero before taking a false start penalty, which didn't sit well with Belichick.

At that point, the clock was down to 5:28.

After being called for two penalties, the Titans were finally going to punt it, but then the Patriots jumped offsides, which allowed the Titans to take the clock down to 5:13. After that penalty, the Titans got another fresh 25-second clock, and by the time they finally snapped it, there was just 4:50 left to play. Including the punt itself, the clock actually ticked down to 4:44, which means the Titans ran a total of one minute and 49 seconds off the clock before the Patriots took possession.

It was time that the Patriots definitely could have used considering their final drive started with just 15 seconds left in the game.

So why were the Titans able to do this?

Thanks to a loophole in the rule book, if the clock is already running, it will continue to run after a penalty as long as there's more than five minutes left in the fourth quarter (Timing rules undergo a slight change late in the fourth quarter with the clock stopping on all penalties once there's under five minutes left in the game).

Belichick definitely knew exactly what Vrabel was doing and that's because he did the same thing just three months ago. Here's how it went down when Belichick used the loophole against the Jets.

With his team leading 33-0 in the fourth quarter against the Jets, Belichick had his punt team burn nearly 90 seconds off the clock, which isn't easy to do, especially when you consider that the standard play clock is only 40 seconds long.

So how did the Patriots burn so much time off the clock?

After the Patriots were tackled in-bounds on a third-and-9 play, the play clock started to run at the 11:04 mark. From there, Belichick decided to let the play clock run out and take a delay of game penalty, which took the game clock down from 11:04 to 10:23. Although Jets coach Adam Gase ended up declining the delay of game penalty, the Patriots were still given a fresh 25-second play clock.

Just as the new play clock got to one second, Brandon Bolden jumped before the ball was snapped, which led to a false start penalty. On the play, it was pretty clear that Bolden jumped on purpose, and if you need proof, just look at the huge smile on his face after the flag was thrown. No one on a Belichick-coached team would smile like that after being penalized unless Belichick asked them to do it.

Brandon Bolden seemed pretty happy about his false start penalty.

After the false start was called, Gase once again declined the penalty, which means the Patriots were once again given a new 25-second play clock. Patriots punter Jake Bailey didn't actually end up kicking the ball until the 9:43 mark, and after the Jets fair catch, New York's offense didn't take the field until the clock was down to 9:37, which means Belichick's plan resulted in a full 1:27 being run off the clock.

As you can see below, Belichick was definitely proud of himself at the time due to the fact that he was able to burn precious time off the clock.

Although the lost time didn't really matter to the Jets -- because they were being blown out -- it definitely mattered in Saturday night's playoff game. Although Belichick and Vrabel both took advantage of the rule this year, there's a good chance that no one will be able to take advantage of it next season, and that's because the NFL could end up closing the loophole.

"That's probably a rule, a loophole that will be closed, and probably should be closed, but right now it's open," Belichick said in October.

Of course, as things currently stand, what the Patriots did in October and what the Titans did on Saturday are both legal and although Belichick was upset during the Patriots playoff loss, he seemed more than happy to take advantage of the rule in October.

"It was just the way the rules are set up," Belichick said at the time. "We were able to run quite a bit of time off the clock without really having to do anything."

Vrabel spent eight seasons playing for the Patriots and on Saturday, he was able to give his former coach a taste of his own medicine.