JACKSONVILLE, Fla. – Dynasties don’t have to be perfect or pretty. They just have to win – like the New England Patriots. The Patriots won their third Super Bowl in four years with a dominant second half last night, wearing down the Philadelphia Eagles 24-21.

It wasn’t overpowering, and at times it was downright ugly. But it was more than enough to match Dallas’s run of the 1990s and certify the Patriots of Bill Belichick and Tom Brady as the NFL’s latest dynasty.

With MVP Deion Branch tying a Super Bowl record for receptions with 11, Brady efficiently running the offense, and Rodney Harrison sparking a smothering defense, the Patriots (17-2) won their ninth successive postseason game, tying the record of Vince Lombardi’s Packers of the 1960s.

The difference once again was an Adam Vinatieri field goal, this one a 22-yarder with 8:40 to go. New England won its other two Super Bowls by the margin of Vinatieri’s last-second kicks.

This time, the Patriots sealed it with a stop. Philadelphia (15-4) got the ball back at its 4 with 46 seconds remaining. It was hardly enough time and far too much territory to cover against such a formidable foe. Harrison snatched his second interception with 9 seconds remaining to end it.

Corey Dillon scored the go-ahead points on a 2-yard run early in the fourth period. And when Branch wasn’t running free, the Patriots flaunted their versatility by again using linebacker Mike Vrabel to find the end zone. Vrabel has caught TD passes in two straight Super Bowls and has five TDs in as many career catches.

Brady wasn’t as fluid as he was when he won the MVP awards in the 2002 and 2004 games, but he was on-target much of the time, finishing 23-for-33 for 236 yards and two TDs.

When the offense bogged down or turned over the ball, Harrison and his mates forced four turnovers, including a goal-line interception by the veteran safety. The Patriots also had four sacks.

And while Terrell Owens’s return from a seven-week injury layoff was an individual success – he had nine catches for 122 yards – it was not nearly the star turn that Branch made. Branch’s 11 catches covered 133 yards, and he was most instrumental on the opening drive of the second half. While New England handled frequent blitzes, Branch caught four passes for 71 yards on the series that ended with Vrabel’s touchdown.

The Eagles showed resilience by responding with a 74-yard drive on which Brian Westbrook accounted for 39 yards, including the 10-yard score. Mc-Nabb whipped a pass over the middle between two defenders for the TD.

But the Patriots reasserted themselves, effectively using screen passes against a tiring defense. Kevin Faulk’s 14-yarder that preceded Dillon’s 2-yard run to make it 21-14.

Vinatieri hit his chip shot to make it 24-14. When the Eagles came back on Greg Lewis’s 30-yard TD reception with 1:48 remaining, things got tight. But when Vinatieri’s kickoff was downed at the 4, the Patriots were able to close it out.

Philly put together the first good drive late in the opening period, and Owens played a big part. He got open on a crossing pattern and gained 30 yards on third down, with a roughing penalty adding 9 yards, but a 16-yard sack by Mike Vrabel set back the Eagles. Then McNabb threw a poor pass that Asante Samuel intercepted in the end zone, only to have it overturned because of illegal contact by linebacker Roman Phifer. No matter. McNabb again threw another duck, which Harrison picked off at the 3.

But Philadelphia’s defense didn’t flinch, and the Eagles got the ball again after a punt. Three plays later, another turnover: Randall Gay knocked the ball loose from L.J. Smith and Samuel recovered at the 38.

Once more, the defense was forced to hold – and did. When the Eagles got the ball back at their 19, they finally finished off a drive.

Todd Pinkston, often overshadowed by Owens, looked like his illustrious teammate on receptions of 17 and 40 yards. On the longer one, he soared high for yet another mis-throw by Mc-Nabb and took it away from Gay.

Westbrook ran to the 6 and on third down, McNabb hung in the pocket and waited for someone to get loose. That someone was Smith in the end zone for the game’s first score with 9:55 left in the half.

It was the first time New England trailed this postseason. The Patriots stayed behind after a rare mistake by Brady. Three plays after Belichick’s challenge overruled a fumble by David Givens, Brady fumbled at the Philly 13 and Darwin Walker recovered New England’s first giveaway of the postseason.

It didn’t lead to anything for the Eagles, and after a 29-yard punt by Dirk Johnson, the Pats drove 37 yards to tie it at 7. Brady found Givens behind Lito Sheppard in the right corner of the end zone for a 4-yard score.