Montreal Impact's Joel Gjertsen celebrates after scoring against Nicaragua's Real Esteli FC during first-half CONCACAF Champions League action in Montreal on Wednesday. ((Graham Hughes/Canadian Press))

The Montreal Impact got off to a good start in the preliminary round of the inaugural CONCACAF Champions League, but they may need an even better finish.

A goal in the 42nd minute from midfielder Joey Gjertsen gave Montreal a 1-0 win against visiting Real Esteli FC at Saputo Stadium on Wednesday, in the first game of the home-and-away series.

Despite controlling the ball in the midfield and creating numerous scoring chances throughout the match, that lone goal was all Montreal could muster in the home half of the preliminary round, which determines a winner using total goals.

As a result, the Impact will take just a one-goal advantage into hostile territory next Tuesday at Carlos Miranda Stadium, in Comayagua, Honduras. The game won't be played in Nicaragua as no stadium there met FIFA norms required for the tournament.

"It's not a great result at home when you should have done better," said Impact defender Nevio Pizzolitto. "We gave away the ball way too much in the second half.

"A bit of lack of concentration could have cost us the game, but we won and if we play well defensively down there, there's no reason we shouldn't win."

The Impact and Real Esteli are among 16 teams from 13 different nations and territories participating in the preliminary stage of the tournament. The eight teams that survive the opening round will join eight teams that received automatic berths in the group stage of the tournament beginning on Sept. 15.

The championship round of the tournament will be played in February 2009 and will feature the top two teams from each of four groups.

Montreal earned the right to be Canada's lone representative in the preliminary round by clinching the Canadian championship on July 22, with a 1-1 tie against Toronto FC of Major League Soccer.

The Vancouver Whitecaps, who compete with the Impact in the United Soccer Leagues, were the third team competing for the Canadian title.

Real Esteli punched its ticket to the Champions League in July with a 1-0 win over Walter Ferreti to conclude a home-and-away series on aggregate goals. The two teams tied 0-0 at Esteli's Independencia Stadium in the first game.

Third time the charm for Gjertsen

Gjertsen finally broke through for the Impact after he had missed on two quality chances earlier in the half. In the 24th minute, he couldn't convert from the edge of the penalty area and he couldn't bury a chance from in close in the 29th minute.

But with minutes to go until halftime, Montreal defender Leo Di Lorenzo crossed a long pass from the left side of the field and in front of the net. An Esteli defender misplayed the ball and his weak clearing attempt landed on Gjertsen's foot at the top of the penalty area.

The American struck a hard, right-footed volley that found the bottom-left corner of the net for Montreal, which held a clear advantage throughout the match over the smaller Nicaraguan club.

Despite Montreal dictating play for most of the match, the Nicaraguan side did have some solid chances in the second half.

Sergio Rodriguez put a free kick on target in the 53rd minute, but it was pushed just wide of the Impact post by Montreal goalkeeper Matt Jordan.

Patrick Luduc, who entered the game late in the first half after teammate Sandro Grande suffered an ankle injury, had a turnover in the 84th minute that could have been costly for Montreal.

The turnover in midfield gave Real Esteli a couple of chances from close range, with Samuel Israel Wilson narrowly missing over the bar on the second shot attempt.

"We think that control of the play was even," said Real Esteli head coach Otoniel Rivas. "We had chances in the second half and didn't score.

"But we didn't show all we have. I think we'll do better in the home leg."

Montreal substitute striker Severino Jefferson had a golden opportunity in the 85th minute to give the Impact a two-goal advantage heading into the second leg of the first round, but he was stopped at point blank range by Real Esteli goalkeeper Carlos Mendieta.

The second half saw five substitutions and the stretcher come out twice for injuries, but the officials only tacked on three minutes of injury time, which drew the ire of Impact head coach John Limniatis after the game.

"I saw lots of amateur situations — from the men in white [the Impact], red and white [Real Esteli] and yellow and black [the officials]," said Limniatis, adding that refs should also have to explain their performances to the media.

"But a win is a win. The 1-0 is better than it seems because it forces them to win a game, and if we can score an away goal, it could be a huge advantage for us."

With files from the Canadian Press