For the fifth time in MLS Cup history, the New England Revolution were forced to watch a celebration they dreamed of participating in. 

This time around, the defeat was a bit more agonizing to swallow. When Chris Tierney's 79th-minute strike found the back of the net, it looked like the Revolution would find a way to score a second goal and lift their first MLS Cup. 

The visiting supporters at the StubHub Center, and the rest of the fans watching back home across New England, were inches away from letting out all of their past failures into one exuberant celebration in the 85th minute. But their celebration was halted when Teal Bunbury's shot from the left wing hit the inside of the top post.

Even after Bunbury's attempt off the crossbar, New England showed no let up in its attacking impetus. With all of the momentum behind them, Jay Heaps' side were poised to break the franchise's final curse. 

Despite all of their offensive efforts, the Revolution could not cover up the one area in which they were exposed all match. 

On Robbie Keane's game-winning goal in the 111th minute, the back four was disorganized and allowed the Irish forward to remain onside. The main player at fault for the goal was Tierney, who was thrust into the role of hero late in the second half. 

With Tierney unable to hold the high line set by the rest of the defense, Keane was able to easily finish past New England 'keeper Bobby Shuttleworth. 

If you watched the match from start to finish, you shouldn't be all too surprised that a defensive lapse eventually cost the visiting Revolution. For most of the match, the Galaxy were able to exploit the massive amount of space between Andrew Farrell and A.J. Soares on the left wing. 

On countless occasions, Farrell seemed lost at his right-back position, which led to Soares shouting instructions at the second-year player after many failed Galaxy attacks. 

Farrell eventually paid for his miscues on Gyasi Zardes' 52nd-minute goal, as he was bested by the movement of the LA forward. To compound his misfortune, the former first-overall pick in the MLS SuperDraft slipped during his recovery. After falling to the ground, all Farrell could do was watch Zardes celebrate in front of the Galaxy faithful. 

The defense was always the weakest link of the Revolution. But in previous rounds, Heaps found a way to cover up the flaws of the back four with a terrific tactical game plan.

In the Eastern Conference Semifinal against Columbus, Heaps employed a high press that caused all sorts of havoc in the Columbus back four. After 90 minutes against the Crew, the Revolution had a 4-2 advantage which was accompanied by four away goals. Earning the key away goals allowed New England to play more relaxed in the second leg and advance to the next round. 

For the second leg of the Eastern Conference Final, Heaps moved Tierney up to the left wing and started Kevin Alston at left-back. The two combined to shut down the dangerous Lloyd Sam, and Tierney played a key role in attack with two assists to earn a 4-3 victory on aggregate.

Despite the explosive offensive showings against Columbus and New York, there were always concerns about the play of Farrell at right-back. The warning signs started to pop up in earnest when Thierry Henry had a pair of good showings against the young Farrell. 

In the four games leading up to the MLS Cup Final, the Revolution relied heavily on the attacking influence of Jermaine Jones. Jones, who changed the dynamic of the team in many ways after his arrival in August, was forced into more of a defensive role for most of the final due to the deficiencies of the back four. 

Although Jones did surge forward during the late bombardment in the second half, he was unable to change the course of the match like he did against Columbus and New York. 

By failing to capitalize on the momentum they created through the first goal, the Revolution were forced to hold off the likes of Keane and Landon Donovan for an extra 30 minutes with a shaky defense. 

The flaws in the defense eventually caught up to the Revolution, but not in a way most expected. It was the consistent Tierney who made the crucial mistake on the eventual game-winning goal. 

There are plenty of positives to take out of the long playoff run made by the resurgent Revs, including the influence of Jones alongside Most Valuable Player candidate Lee Nguyen in midfield. 

However, if New England wants to eventually get over the hump and win its first MLS Cup, improving the defense must be the top priority in the offseason. 

Follow Joe on Twitter, @JTansey90. 

Read more MLS news on BleacherReport.com

Source: Click Here