Here's a viewer's guide to the MLS playoffs' conference semifinals.

All four series will be played over two legs, home and away, with away goals counting as the first tiebreaker. The first legs will be played on Sunday. Three of the four second legs will be played the following Sunday, Nov. 11. Western Conference No. 2 seed Seattle will play its home game on Thursday, Nov. 8 because of another event at CenturyLink Field.

E1. New York Red Bulls vs. E5. Columbus Crew

First leg: Sunday, 3 p.m. at MAPFRE Stadium, Columbus (ESPN and ESPN Deportes, ESPN.com/Watch)
Second leg: Nov. 11, 7:30 p.m. at Red Bull Arena, Harrison, N.J. (Fox Sports 1, Fox Deportes, FoxSportsGo.com)

Red Bulls player to watch: F Bradley Wright-Phillips

Few players have been more responsible for the Red Bulls' consistent success in recent times than the English striker. He has 126 goals in all competitions in his six seasons in MLS, including nine in the playoffs, and three Supporters' Shields. But he still lacks the biggest prize of all, as do the Red Bulls as a whole. Will this finally be the year when they win MLS Cup?

Columbus player to watch: GK Zack Steffen

The Coatesville native's heroics in the first-round penalty shootout win over D.C. United further burnished his reputation as the U.S. men's national team's top goalkeeper. If he can help the Crew get a result in the first leg, the pressure on New York coming home will be impossible to ignore.

E2. Atlanta United vs. E3. New York City FC

First leg: Sunday, 7:30 p.m. at Yankee Stadium, New York (Fox Sports 1 and Fox Deportes, FoxSportsGo.com)
Second leg: Nov. 11, 5:30 p.m. at Mercedes-Benz Stadium, Atlanta (ESPN, ESPN Deportes, ESPN.com/Watch)

Atlanta player to watch: F Josef Martínez

He won the Golden Boot by a mile, setting an MLS single-season scoring record with 31 goals. But there's a caveat: He scored just three times combined in July and August. One came in the regular-season-ending 4-1 loss at Toronto FC that cost Atlanta the Supporters' Shield. But will it get him back on track? And will he be able to break free amid Yankee Stadium's tight confines?

New York City player to watch: F David Villa

As annoying as it is to watch soccer in a baseball stadium, the star power of this series is impossible to ignore. Villa looked like his old self in NYCFC's two wins over the Union, rampaging through the back line in harmony with Maxi Moralez. The Spanish legend can dish out a good assist, too, as he showed with his backheeled flick to Ismael Tajouri-Shradi in the playoff game.

W2. Seattle Sounders vs. W5. Portland Timbers

First leg: Sunday, 5 p.m. at Providence Park, Portland, Ore. (ESPN and ESPN Deportes, ESPN.com/Watch)
Second leg: Nov. 8, 10:30 p.m. at CenturyLink Field, Seattle. (Fox Sports 1 and Fox Deportes, FoxSportsGo.com)

Seattle player to watch: F Raúl Ruidíaz

Stefan Frei might win Goalkeeper of the Year, and Chad Marshall has a shot at Defender of the Year, but would the Sounders be where they are if they hadn't signed Ruidíaz in late June? Do you remember how toothless their attack looked before he arrived? They were shut out 10 times in 23 games in all competitions before his debut July 21. The Peruvian has 10 goals in 14 games in rave green, including both tallies in the 2-1 win on the last day of the season that sealed a first-round bye.

Portland player to watch: M Diego Valeri

Because of this …

… and this …

… and everything else Portland's midfield maestro does as one of MLS' most entertaining players. He'll be at center stage once again amid the drama and spectacle of American club soccer's most famous rivalry.

W1. Sporting Kansas City vs. W6. Real Salt Lake

First leg: Sunday, 10 p.m. at Rio Tinto Stadium, Sandy, Utah (Fox Sports 1 and Fox Deportes, FoxSportsGo.com)
Second leg: Nov. 11, 3 p.m. at Children's Mercy Park, Kansas City, Kan. (ESPN and ESPN Deportes, ESPN.com/watch)

Kansas City player to watch: M Johnny Russell

Most Union fans will probably watch American football instead of the world's football Sunday, but they'll find a lesson in this game. While it's fair to complain that the Union don't spend as much as Atlanta and the New York teams, it's even more fair to complain that they haven't been as good at scouting under-the-radar foreign signings as Sporting has.

Russell, a Scotland native, is a great example. He came from English lower-division club Derby County, recorded 10 goals and 10 assists this year and, because of his good form, earned a first call-up to Scotland's national team in three years.

Real Salt Lake player to watch: M Damir Kreilach

Here's another team that nails its foreign scouting far more often than it doesn't. RSL found Kreilach, a Slovakia native, in Germany's second division. He's played in 34 games this year, has 14 goals, and was the star of Wednesday's upset of star-studded LAFC in Los Angeles.