Ask Minnesota United players or coaches about the Ottawa Fury, their opponent in Sunday's NASL semifinals, and they tend to use the same word: disciplined.

The Fury has earned that respect this year, as its defense allowed just 23 goals —seven fewer than the next-best defense. Fury goalkeeper Romauld Peiser might be the favorite for the league's MVP award, thanks to a combination of stunning saves and his command of what has become the league's best back four.

No NASL experts picked Ottawa to land anywhere near the playoffs, never mind tying for the most points in the league, but the Fury closed the season with an astonishing run in which it lost just once in 25 games. Fittingly, though, that loss was at home to Minnesota — setting the stage for a playoff rematch.

The Loons did not have near the defensive success that the Fury did this year, but they have tried to play a similar style. In three matches against Ottawa this season, Minnesota chose to stay compact defensively, cutting off the middle of the field and pushing attacks to the wings. This left the Fury to serve countless crosses into the penalty area, searching for 6-4 center forward Tom Heinemann.

In general, Heinemann and the off-side winger will make runs into the opposing team's box, with the team's attacking midfielders supporting the offense and hoping to create enough chaos for a bounce or break to turn Ottawa's way. It will be up to United keeper Sammy Ndjock to play a commanding, mistake-free game, and to the Minnesota defenders to clear the ball before the Fury has chances to score.

This careful, defense-first approach tends to leave United without the ball for long stretches. United has pressed some of the league's less-skilled teams high up the field, seeking to control possession and attack through passing, but against Ottawa that all took a back seat to a defense-first approach.

Brian Stensaas — Associated Press, Star Tribune

The three goals United scored against the Fury this year came from a terrible defensive turnover by Ottawa, a free kick, and a 50-yard pass over the top of the defense. While opportunistic, the three goals also speak to the fact that the Loons have struggled to break through the Ottawa lines on the offensive end. If the past is an indication, Minnesota will settle for being defensively responsible — and ready to pounce when a small opening comes its way.

With discipline on both sides of the ball, it would be reasonable to expect this game to come down to a couple of key moments. One foul in the penalty area could be the difference, or one free kick given away in an attacking position, or one mistake in the defensive half of the field.

Sunday's winner will be the team that doesn't make mistakes — and makes the other team pay for theirs.

SHORT TAKES

• It's a good bet that at least one of the MLS conference semifinals will be decided by the most illogical of tiebreakers: the away-goals rule. If any of the two-legged matches, which conclude Sunday, are tied at the end of regulation, the winner will be the team that scored the most goals away from home. Introduced a half-century ago in Europe, the rule is a relic of a time when travel was arduous and road wins were rare. It's time to stop using it in all soccer, not just MLS.

• It might be hard to believe, but the U.S. Men's National Team begins qualifying for the 2018 World Cup this week.

The U.S. will play St. Vincent & The Grenadines in St. Louis on Friday night, and is heavily favored to advance out of its four-team group to make the final round of qualifying, which will begin next November.

• The Gophers women's soccer team will find out Monday afternoon if it qualifies for the NCAA tournament. Minnesota led the Big Ten with two weeks to go, but lost three of its last four regular-season games to finish sixth, then lost 4-1 to Rutgers in the Big Ten quarterfinals.

Weekend watch guide

• Premier League: Chelsea at Stoke City, 11:30 a.m. Saturday, Ch. 11. Chelsea's stunning losing run continued last week with a loss to Liverpool, and now, some media outlets are suggesting that Jose Mourinho may have one week left to save his job. Will this be the last time we see the man who labeled himself "The Special One" in England?

• Premier League: Tottenham at Arsenal, 10 a.m. Sunday, NBC Sports. Big games come and go, but the North London derby remains. Tottenham has only won one away game in this matchup in the past 20 years. That said, Spurs striker Harry Kane has four goals in his past two league games, after a very slow start to his second season.

• NASL: Minnesota at Ottawa, 2 p.m. Sunday. Last year, United's excellent season ended in the semifinals, with a loss to in a penalty shootout with Fort Lauderdale. It made what was perhaps the team's best-ever season seem like it was in vain — and it's focused the Loons on trying to prevent the same thing from happening this year.

• MLS: Seattle at Dallas, 6:30 p.m. Sunday, Fox Sports 1. Seattle leads this playoff matchup 2-1, after a late Clint Dempsey free kick gave it the victory in the first leg at home. Now, the Sounders have to try to hold on in second leg — and Dallas will be at home, where it has lost only twice in 17 games this season.