After some crazy knockout-round matches this week, Major League Soccer's conference semifinals are set.
All of the first-leg matches will be played this Sunday, with the second-leg games set for next week.
A look at the four matchups by conference:
EASTERN CONFERENCE:
(2) ATLANTA UNITED vs. (3) NYCFC
The highest-scoring team in MLS, Atlanta United, will face the third-highest scoring team in the Eastern Conference in NYCFC in the semifinals. NYCFC advanced from the knockout round with a 3-1 win over Philadelphia on Wednesday.
Atlanta was in the race for the Supporters' Shield up to the final day of the regular season, but fell short after losing 4-1 at Toronto. Still, slowing down Atlanta's scoring machine and the duo of Josef Martinez and Miguel Almiron will be a challenging prospect for NYCFC. Martinez won the Golden Boot with a league-record 31 goals, while Almiron had 14 assists and was just as important in making Atlanta's attack so dangerous.
NYCFC got one goal from David Villa in the win over Philadelphia but needs to continue getting contributions from Maxi Moralez and Ismael Tajouri-Shradi, who also scored against the Union.
The two regular-season matchups between the sides ended in ties. They played a 2-2 draw in Atlanta in April and finished 1-1 at Yankee Stadium in early June.
1. NEW YORK RED BULLS vs. (5) COLUMBUS CREW
The winners of the Supporter' Shield will face the feel-good story of the Eastern Conference playoffs. Columbus secured its spot in the postseason on the final day of the regular season then ousted D.C. United on penalties in the knockout round thanks to another tremendous performance from goalkeeper Zack Steffen. It's been a special closing stretch to the season for the Crew, making the playoffs and seeming to have their long-term future secured in Columbus with new ownership.
It's been a special season for the Red Bulls as well, capturing the Supporters' Shield for the third time since 2013. But the previous two times the Red Bulls won Supporters' Shield they failed to make MLS Cup. New York was knocked out in the conference semifinals by Houston in 2013 and beaten by Columbus in the Eastern finals in 2015.
Red Bulls will certainly have an advantage in the first leg despite being on the road after Columbus had to play 120 minutes and go to penalties to advance from the knockout round.
Columbus does have a win this season at Red Bull Arena, beating New York 3-2 in late July. The teams played to a 1-1 draw in Columbus in early June.
WESTERN CONFERENCE
1. SEATTLE SOUNDERS vs. (5) PORTLAND TIMBERS
The Sounders got to rest in the knockout round after wrapping up the regular season with a 2-1 victory over the San Jose Earthquakes. The win, secured on a Raul Ruidiaz stoppage-time goal, combined with Colorado's Decision Day victory over FC Dallas, slid the Sounders into second place in the standings.
The Sounders won 14 of their final 16 games in another remarkable second-half surge under coach Brian Schmetzer.
Portland lost its final regular-season match against the Whitecaps and had the daunting task of facing FC Dallas on the road in the knockout stage. But the Timbers pulled off a 2-1 upset with a pair of goals from Diego Valeri, despite playing for much of the second half a man down.
The victory set up the Cascadia semifinal between the two teams, who last met in the 2013 conference finals with Portland winning 5-3 on aggregate.
The two teams met three times during the regular season, but Seattle won the last one 1-0 at Providence Park.
Portland will be without Larrys Mabiala after he was sent off with a red card in the match against Dallas.
1. SPORTING KANSAS CITY vs. (6) REAL SALT LAKE
Real Salt lake has been the surprise of the playoffs. First the team snuck into the postseason despite being the only league team that didn't play on Decision Day, earning the sixth and final seed by virtue of the LA Galaxy's meltdown at home against the Houston Dash.
Then they stunned LAFC 3-2 in a knockout round match Thursday night in Los Angeles. Jefferson Savarino's shot deflected off Walker Zimmerman's head in the 69th minute for the winning margin. LAFC fans at Banc of California Stadium did not react well, some shouting an offensive slur and throwing items on to the field.
But RSL will face a much greater challenge in Sporting, which has won three straight and led the Western Conference (and was second in the league) with 65 goals, a club record. Kansas City secured the top seed with a 2-1 Decision Day victory over LAFC.
The two sides are meeting in the postseason for the first time since their tense 2013 MLS Cup final, which Sporting won on penalties after a 1-1 draw.
The teams met twice this season in league play, with RSL winning 4-1 at Rio Tinto Stadium in July, and a 1-1 draw in Kansas City in late September.
Sporting will be without Seth Sinovic, who was sent off with a red card in the regular-season finale.
