MONTREAL - The Jekyll-and-Hyde Montreal Impact are in Philadelphia Saturday (7:30 p.m.), hoping to shed their reputation for being unable to win in stadiums not named after cheese companies.

The first-place Impact, who have won regularity at their home Saputo Stadium, have not managed a win on the road in their last five tries, managing just two points over that span.

The Impact (12-7-5) owe their first-place standing on their solid play in Montreal but hope to surf on the momentum 5-0 home laugher over the Houston Dynamo last Saturday.

The Philadelphia Union are led by Jack McInerney, who has netted 10 goals, but has cooled off since a torrid start. Conor Casey has picked up the slack, scoring nine markers on the year while Union midfielder Sébastien Le Toux leads the league with 12 assists.

The Union have a 6-3-4 home record and currently sit in fourth in the Eastern Conference.

The Impact have been led by a potent offence and a middling defence. Their scoring has been generated primarily by Marco Di Vaio, who leads the league with 15 markers.

Di Vaio owes many of those goals to Justin Mapp, who has become an MLS star this year with some impressive passes and attacks. Mapp might be further motivated to beat the Union, one of his former teams.

The Impact are expected to go with a 4-4-1-1 formation with starters Troy Perkins in nets, along with Camara, Ferrari, Nesta, Brovsky, Bernier, Bernardello, Mapp, Romero, Felipe and Di Vaio.

The Impact beat the Union 5-3 in the only prior showdown between this teams this season.