MONTRÉAL - Saturday's game between the Union and Impact was rightly billed as a showdown between Major League Soccer's two hottest scorers: Philadelphia's Jack McInerney and Montréal's Marco Di Vaio.

The duel didn't take long to live up to the hype. But by the end of a cold, rainy night at Stade Saputo, it proved to be a massacre.

Though McInerney scored his ninth goal of the season, Di Vaio responded with a majestic first-half hat trick that propelled the Impact to a 5-3 rout of the Union.

"It was as bad as it's ever been," Union manager John Hackworth said. "It's really unfortunate that we ended up like this, because we felt that we could go nose-to-nose with these guys."

Coming into the night, Hackworth had reason to believe that. The Union sat just two points behind the Impact before kickoff, and would have jumped over them into fourth place in the Eastern Conference with a win. As it stands the Union now remain in fifth place - the last playoff spot in the Eastern Conference.

The top five teams in each conference qualify for the postseason, a feat the Union have achieved just once in their history so far.

Di Vaio got the Impact on the board barely two minutes into the game, rocketing in a low shot from the edge of the 18-yard box. The assists went to two players whose names are well-known to Philadelphia fans by now: Lititz, Pa., native Andrew Wenger and former Union midfielder Justin Mapp.

Three minutes later, the Union responded in style. Sébastien Le Toux took a cross from Sheanon Williams and laid it off to Michael Farfan with a backheel flick, and Farfan found a totally unmarked McInerney with a cutting pass six yards from goal. The 20-year old pounced on the chance and scored his ninth goal of the season.

The game settled down for a while after that, but in the last 15 minutes Di Vaio stormed back into the spotlight. He carved up the Union's defense for two goals in quick succession, scoring in the 28th and 32nd minutes. By halftime, the drenched crowd of 17,104 was chanting the Italian's name in unison.

"To allow [Di Vaio] to get free the way we did, especially in the first half, is unacceptable on so many levels," Hackworth said. "It was one of the major points of emphasis and we just did a really poor job on him all night long."

McInerney and Di Vaio now share first place in MLS's scoring charts with nine goals each. In a way, it's a metaphor of the league's stature in its 18th season.

Di Vaio is MLS' fifth-highest paid player, with a salary of over $1.9 million. He has fully justified that big paycheck, scoring goals and winning acclaim in a market with a sizeable Italian expatriate population.

McInerney is just 20, and his salary is 1/10th of Di Vaio's. But the Chattanooga, Tenn., native's red-hot start to the season has made him a potential target to make the U.S. national team roster for July's CONCACAF Gold Cup.

In the 69th minute, substitute Antoine Hoppenot brought the Union back into the game with a goal seemingly out of nowhere. After an incisive run down the right wing, the Princeton product hit a cross that surprisingly swung back towards goal and into the net.

But five minutes later, Wenger returned the Impact to a two-goal advantage, heading in a corner kick from Brazilian playmaker Felipe Martins.

Sébastien Le Toux gave Union fans another chance to hope for a come-from-behind stunner in the 85th minute, when he cut the Impact's lead to 4-3. After some fancy footwork that left Mapp going backwards, Le Toux hit a left-footed rocket past Impact goalkeeper Troy Perkins.

The Union surged forward in search of an equalizer, but it never came. Instead, rookie Blake Smith scored the Impact's fifth goal of the night, racing down the left wing on a counter-attack and calmly slotting the ball past MacMath.

"We tried to come back in the game, [and] we certainly did that," Hackworth said. "We really, really mis-managed that last part for sure."

While the team has made significant progress this year compared to 2012, its current place in MLS is one of solid mediocrity. The Union have four wins, three draws and one loss against teams not currently in playoff spots, but just one win and four losses against teams that would make the postseason if it started now.

"Our record is what it is," McInerney said. "If we want to make the playoffs, if we want to do something, we need to beat teams like Los Angeles and Montréal. It's just getting that first one out of the way, and getting some confidence that we can carry into other games."

The Galaxy and Impact have dealt the Union their two worst results of the season: a 4-1 loss at PPL Park on May 15 and Saturday's loss, respectively.

An eight-goal game may be great entertainment for neutral fans, but for the Union Saturday night was long and frustrating. The team's entire defense failed to cope with Montréal's pace and pressure. With little depth available after trading Gabriel Farfan and Bakary Soumaré, manager John Hackworth had little choice but to sit and watch.

"If one guy's having a bad night, it really affects us in a negative way," Hackworth said. "We need to make some moves maybe, going forward, and we have the spots and a little bit of space to do that now. We're certainly looking."

One of those moves could be trading to bring back former Union captain Danny Califf. He has fallen out of favor at Toronto FC - which happens to be the Union's next MLS opponent, on June 2.

Before then, though, there's a U.S. Open Cup home game against the Ocean City Nor'easters at PPL Park on Tuesday. That will give the Union an opportunity to quickly put Saturday's rout out of mind.