Graham Zusi is a big reason why Sporting Kansas City has posted back-to-back victories for the first time. His role on the club just got even more important with the departure of Ryan Smith.

Zusi looks to continue his stellar play and help Kansas City become the first team to win on the road against the Philadelphia Union on Wednesday night.

Kansas City (3-6-4) has followed an 0-6-4 stretch with strong performances in its last two games, winning 4-1 on the road over FC Dallas on June 12 and 1-0 at home over San Jose last Friday.

"What I would say to you is that this group has never lost the belief that they could play," manager Peter Vermes said. "They know they're a good team and now it is about grinding out results."

Zusi had two goals and an assist against Dallas and assisted on C.J. Sapong's winner versus the Earthquakes. He's started the last five games for Kansas City.

"He's dangerous," Vermes said. "I think teams are now starting to see what we've seen all along. We've just been looking for it on a consistent basis and now we're starting to see that."

Vermes replaced Smith with Zusi in a 1-all draw with Colorado on May 28, and Kansas City is 2-0-3 since that move.

Kansas City announced Tuesday that Smith will be leaving the team for the rest of the season due to family reasons, with Vermes saying the English midfielder needs to be closer to home. Smith missed the first four games after offseason knee surgery and sat out the past three matches with a groin strain.

That puts more of the playmaking onus on Zusi, who totaled one goal and one assist over his previous two seasons with Kansas City.

"I've kind of found myself in a role where I'm getting some more starts," Zusi said. "That always builds some confidence as it is. Every game we seem to be getting better and I think the whole team is playing with more confidence now."

Kansas City is 0-4-2 against Eastern Conference opponents, but went 1-0-1 against Philadelphia (6-4-4) in 2010.

The Union, 4-0-3 at home, will be trying to bounce back from a 1-0 loss to Vancouver on Saturday. The expansion Whitecaps had been on the third-longest winless streak in MLS history at 14 games.

"It was a good fight and we missed a couple of good chances, but we just weren't lucky," coach Peter Nowak told the Union's official website. "We're like a charity giving up (chances to score) goals. The team worked very hard and we put so much effort into it and we didn't get rewarded."

Philadelphia has scored twice during an 0-2-1 stretch this month. The club will welcome the return of Carlos Ruiz, who is expected back from international duty with Guatemala for the Gold Cup.

Top goal scorer Danny Mwanga came off the bench against Vancouver, and he or Ruiz could be added to the starting lineup.