After opening the season with a win over the defending MLS Cup champions, the Seattle Sounders couldn't close out their homestand with another victory.
The Sounders weren't as successful shutting down Toronto FC last Saturday, allowing two goals in the first 24 minutes en route to a 2-1 defeat. Dempsey scored for Seattle (1-1-0) in the 68th minute, but cameras also caught him hitting Mark Bloom in the groin with his right hand late in the first half.
The Seattle forward claimed he was trying to knock Bloom's hand off his back and later apologized to the Toronto defender.
"I tried to hit it away and thought I was hitting his hand away," Dempsey said. "I understand that maybe I did catch him a little bit. I apologized to him about that, but for me, all I was trying to do was smack his hand from touching my back."
That apology, however, did not help Dempsey avoid a two-game suspension.
Montreal (0-2-0) is already accustomed to playing short-handed. The Impact are without Di Vaio, third in MLS with 20 goals in 2013, and midfielder Andres Romero for the first three games because of their involvement in a shoving match with Houston players in last year's 3-0 loss in the knockout round of the playoffs.
Sanna Nyassi and Andrew Wenger scored in the March 8 opener against FC Dallas as Montreal suffered a 3-2 defeat. Nyassi injured his left knee in that game and is expected to miss at least the next two weeks.
With those absences piling up, Montreal fell 1-0 to the Dynamo last Saturday on a goal in the 40th minute after the ball went off defender Eric Miller's foot.
The Impact are hoping a return home will help them break their worst start in the franchise's three MLS seasons. They went 0-4-1 to start their inaugural 2012 campaign, earning the draw in their second game, and began 2013 with four straight wins.
"It's good that we're finally here and we'll get that support for 90 minutes," first-year coach Frank Klopas said. "To have the support of the fans gives you a different lift, an emotional lift."
The Impact are 2-0-0 in the all-time series, opening last season with a 1-0 victory in Seattle and posting a 4-1 rout in Montreal on June 16, 2012.