[CONCACAF CHAMPIONS LEAGUE] Seldom in its four seasons of play has the Houston Dynamo shown any reluctance to attack, but like any team, it has struggled through periods of slack finishing. That won't be an option if it wants to prevail in the quarterfinal, second leg with Mexico's Atlante in Cancun on Tuesday (10 p.m. ET, Fox Soccer Channel, Telefutura).

Early in the 2007 MLS season, Houston scored just one goal in four games, awoke to beat Colorado, 3-1, then slipped back into a slump with just one goal in the next three matches. Then it reeled off an eight-game unbeaten run while scoring 16 goals, and eventually finished in the middle of the MLS pack - sixth - in scoring with 43. It rode to a second straight league title mostly on its defense, which set a league mark by conceding only 23 goals.

Houston will need to both score goals and stay tight at the back to have any chance of progressing in the Concacaf Champions' League. Squandered opportunities in the first leg haunt the Dynamo as it prepares to take on Mexican club Atlante in the second leg of their quarterfinal series in Cancun Tuesday (10 p.m. ET, Fox Soccer Channel, Telefutura) tied, 1-1.

One change implemented when Concacaf expanded the Champions' Cup to the Champions' League last season was to count away goals scored in regulation as a tiebreaker; thus, if the second leg ends goalless, Atlante wins on away goals. A 1-1 tie in regulation will force overtime. Any higher-scoring tie in regulation, or a Houston win, sends the Dynamo to the semifinals to meet either Montreal or Santos Laguna, which play their second leg Thursday with Montreal leading, 2-0.

If any team can score goals on the road in Mexico, it's Houston. It lost 5-4 on aggregate to Pachuca in the 2007 Champions' Cup despite scoring two away goals, and last year played a spectacular 4-4 tie against UNAM in Mexico City during the SuperLiga tournament.

"We know what we have to do," said forward Brian Ching, who scored his first two goals of the preseason in a 3-2 friendly defeat of USL-1 Montreal on Saturday. "No MLS team has won down there before, so we know it is going to be a big task. We are a confident team. We are going to go down there and give it everything."

Ching will be a pivotal figure in the Dynamo attack, which breached Atlante several times in the first half of the first leg yet scored only once, when Bobby Boswell nailed home a Brad Davis corner kick in the 34th minute. Stuart Holden missed a pair of good opportunities; Kei Kamara headed a shot off the crossbar and with another header forced a good save from Atlante goalie Omar Ortiz, whose intermittent shaky handling and hesitant decision-making Houston failed to exploit.

With sharper finishing, Houston might have approached or even matched the 4-0 thumping it handed Atlante last year in the SuperLiga, which occurred early in preseason for the Mexican teams. This time around, Atlante is the team in the middle of its regular season.

Key players for both teams return for the second leg after serving one-game suspensions. Houston coach Dominic Kinnear must decide if defender Eddie Robinson will return to his regular spot in the middle alongside Boswell, or if second-year man Julius James is the better option. First-team Atlante keeper Frederico Vilar is eligible to play.

Atlante is mired in two droughts of its own. A 0-0 tie with Cruz Azul in Mexico City on Saturday extended its winless streak in league play to six matches, during which it has scored only three goals.