MONTREAL -- C.D. Olimpia of Honduras scored two crucial away goals and defeated the Montreal Impact 2-1 in the opening leg of the CONCACAF Champions League quarterfinal on Tuesday.

Jerry Bengtson and Jorge Benguche scored in the first half for Olimpia (1-0-2), who eliminated the Seattle Sounders in the round of 16.

Saphir Taider got one back for Montreal (0-1-2) in the second half after going down 2-0. It was Thierry Henry's first loss as Impact head coach.

The return leg is next Tuesday in Honduras, where Montreal will need to win to stay alive in the competition.

Down 2-0, Henry made a tactical change at halftime to shake things up. He went from a 5-3-2 formation to a 4-3-3. Orji Okwonkwo entered the game for Zachary Brault-Guillard and provided an offensive spark.

The move paid instant dividends when Taider scored a sensational goal from 35 yards out in the 47th minute. Taider took a bouncing ball from Okwonkwo in stride and fired a perfectly weighted shot that dipped past the diving goalkeeper.

That goal livened up the 20,243 fans at Olympic Stadium, who had grown quiet in the first half.

Montreal had a chance to tie the game in the 70th minute with a free kick on the edge of the penalty box but Taider sent the ball over the bar.

Another opportunity in the 76th was wasted when substitute Anthony Jackson-Hamel, unmarked in the box, sent his header wide.

It appeared the Impact were awarded a penalty kick in the 81st when Jackson-Hamel's header went off Maylor Nunez's arm in the box. Referee Adonai Escobedo pointed to the spot but later changed his decision after consulting the assistant referee.

It was only the second loss for Montreal on home soil in the Champions League (9-2-3).

The Impact saw a lot of the ball in the opening minutes. They strung several passes together in Olimpia's half but couldn't enter the final third.

Olimpia goalkeeper Edrick Menjivar pulled his groin on a goal kick early in the match. He was replaced by substitute 'keeper Alex Guity.

The defending Honduran champions scored off Guity's ensuing goal kick in the 15th minute.

The ball fell to Leonardo Garrido, who headed it into the path of Bengtson. On poor coverage by rookie Luis Binks, Bengtson snuck behind the defenders and shot the ball with his first touch. Clement Diop got his hand on it, but not enough.

Instead of sitting back, the visitors kept looking for holes in the Impact back line, especially on the counter.

That second away goal came in the 41st minute. After a poorly taken Impact free kick, Olimpia marched down the field with speed. Benguche evaded a tackle from Brault-Guillard with a dummy before beating Diop far side.

The winner of the two-legged aggregate series will face New York City FC or Mexico's Tigres in the semifinal next month.