The high-scoring Portland Timbers were blanked in their last match, but they continue to shut down their opponents.
That's especially been the case at home, where they haven't conceded a goal in six league matches.
Portland will try to extend its franchise-best unbeaten stretch to 15 on Sunday against a Colorado Rapids team that's hit a rough patch following its best run of the season.
Among the MLS leaders with 25 goals, the Timbers (6-1-9) were shut out for the second time this season Wednesday in a scoreless draw at Los Angeles.
Portland, though, has recorded shutouts in four of its last six league matches and has seven this season.
"I think what's great is that we lead the league in goals and everybody talks about our attacking side but we're becoming a very good defensive team," coach Caleb Porter told the Timbers' official website.
The last goals Portland allowed at Jeld-Wen Field in MLS play were in a 2-1 loss to Montreal on March 9. The club has gone 6-0-8 overall - and 4-0-1 at home - since.
"It's crazy how it works, we have so many guys going in and out on the backline and we still manage to put up shutouts," defender Andrew Jean-Baptiste told the league's official website.
Since Milos Kocic saw his first action of the season in place of Donovan Ricketts (international duty) in a 2-all draw at Chicago on June 8, Ricketts has posted back-to-back clean sheets. He's blanked his last three opponents and needs to go seven minutes without a goal allowed for his longest shutout streak of the season at 313.
Ricketts was beaten by Colorado's Dillon Powers and Hendry Thomas (penalty kick) on March 30, but the Timbers salvaged a 2-all draw with midfielder Will Johnson netting two second-half goals, including a penalty kick.
The Rapids (5-6-5) surrendered just three goals in their next eight games - going 5-1-2 in that stretch - but they've allowed two in each of their last three.
"I think it's a bunch of little things," coach Oscar Pareja, who served a one-game suspension in Wednesday's 2-1 loss at the Fire, told the Rapids' official website. "We can't point out just one, because when you attack or when you defend it's a collective effort and we attack as a unit and defend as a unit."'
Thomas and midfielder Atiba Harris, the team leader with four goals, are eligible to return following suspensions, but with the Rapids playing their third match in nine days, Pareja could tinker with his lineup.
"The good thing is that we're deep," he said. "We have some players that can bring some fresh legs for sure, so we are considering (resting players)."
The Timbers are 1-1-0 as the home team in this series following a 1-0 victory Aug. 31.