Sam Ortega/Portland Timbers

The Portland Timbers' unbeaten streak, 11 games in MLS play, 13 in all competitions, will be on the line and in serious jeopardy on Sunday afternoon, shortly after the conclusion of the World Cup final, when the Timbers take the field in Los Angeles to face a red-hot LAFC looking to jump to the top of the Western Conference (3:00 p.m., TV on ESPN2).

The Opponent

When LAFC visited Providence Park back in May, they did so without the services of a center forward —Marco Ureña was out injured, and Adama Diomande had not yet arrived from Hull City — and the Timbers benefited in what was a humdinger of a 2-1 win.

With a center forward in the lineup, either Ureña or Diomande, LAFC has been absolutely murderous: 9-2-1, versus just 1-2-3 when playing a false nine. They're 4-0-1 in their last five in league play.

That's thanks in large part to Diomande, who has been an absolute terror since debuting at the end of May. Reunited with Bob Bradley, under whose direction he enjoyed the best spell of his career three years ago at Stabaek, he's banged nine goals in his first seven MLS games, with five in his last three outings.

Diomande is staying in the lineup, even with Ureña back from the World Cup. Carlos Vela, meanwhile, will have no such problem getting back into the team now that he has returned from Russia, while the club's third DP, Portuguese midfielder Andre Horta, is eligible to play for the first time on Sunday.

This team is on pace to be the best and highest-scoring MLS expansion side ever, and they're the odds-on favorite to win the Western Conference.

The Tactics

Bradley has favored a 4-3-3 nearly all year, save for a stretch of spring road games in which he used a five-man back-line, and that's the formation we'll see this weekend. His headache, thanks to the arrival of Horta and return of the World Cup contingent, will be in selecting his team.

Eventually, there might not be places for the likes of Latif Blessing and Mark-Anthony Kaye — key contributors all year, and especially in the last month — but they way that LAFC plays isn't going to change.

They endeavor to get the ball to their creative players in high-leverage situations, and move freely and quickly off of them. The fullbacks get forward consistently, and the center backs take big risks — for better and worse — in the open field.

It's not at all how the Timbers approach games, and LAFC is going to have a significant advantage in possession on Sunday.

The big question for Giovani Savarese is whether to stick with the 4-4-2 diamond that the Timbers have used to victories in back-to-back weeks against Seattle and San Jose, or add another player in midfield to help combat LAFC's pressure.

The game in May was a fast-paced, fairly contentious affair that with Bradley jawing at Savarese after the final whistle. The heat in LA on Sunday (it's expected to be around 85 degrees at kickoff) might slow both teams down some, but it should be another excellent contest.

The Lineup

1 - Attinella
16 - Valentin
18 - Cascante
33 - Mabiala
2 - Powell
13 - Olum
21 - Chara
14 - Flores
10 - Blanco
8 - Valeri (C)
99 - Armenteros

— The Timbers lineup seems fairly settled at the moment, especially in defense — where Vytas and Liam Ridgewell remain on the outside looking in.

— Lawrence Olum, who has started four straight games, seems to have locked down his place as the base of midfield.

— Should Savarese decide to remove Dairon Asprilla for another midfielder, Andres Flores, Cristhian Paredes, David Guzman, and Andy Polo would all be options to start, though Polo hasn't played 90 minutes since the last LAFC game in mid-May and Paredes is coming off of an injury that kept him out of the San Jose game.

The Memory

Samuel Armenteros came up with the game-winning assist the week prior against Seattle, but it was his sensational solo goal to win the game between these two teams in May that truly announced his arrival in Portland.

The Pick

The inverse of the game in Portland: LAFC 2, Timbers 1.