[MLS] Will the fourth time be the charm for Seattle when it faces Los Angeles in the conference semifinals, second leg Sunday (9 p.m. ET, ESPN/ESPN Deportes)? The Galaxy has won all three meetings in league play this year, including a 1-0 victory last week in the first leg.

Galaxy coach Bruce Arena got a shutout in Seattle with a revamped back line, but could make that unit even stronger.

Left back Todd Dunivant missed the first leg with a strained hamstring, yet has trained all week and is ready to claim back the spot from veteran Eddie Lewis. Arena slotted in Lewis, who has announced his retirement effective at the end of the season, despite him not having started a match since the season opener more than seven months ago.

A savvy performance by Lewis helped contain Sounders’ right midfielder Sanna Nyassi. Coupled with a solid defensive stance on the opposite flank against Steve Zakuani, and A.J. DeLaGarza manning the middle in place of injured veteran Gregg Berhalter, the Galaxy blunted Seattle’s potent attackers for most of the match.

A bigger playing surface at Home Depot Center for the second leg might give the Sounders more space, yet the same will be true for Landon Donovan and David Beckham. They dropped into defensive positions for much of that game and will do so again if necessary unless the Galaxy falls behind or even on aggregate and needs to score.

Given that the Galaxy outside pair are probably superior to their Seattle counterparts, the Sounders need sharper, tougher play from forwards Fredy Montero and Blaise Nkufo as well as some incisive pressure by central mids Nathan Sturgis and Oswaldo Alonso. Montero got only two good looks at goal in the first leg and drifted out of the play numerous times. The Galaxy is one of the league’s most dangerous teams on the counterattack and forward Edson Buddle’s knack at getting in behind defenses makes the risks Seattle must take even more dangerous.

“We know it’s going to be tough,” said Buddle, whose remarkable, looping strike that found net in the first leg has been decried as a fluke by some – such as Sounders coach Sigi Schmid -- but praised by others, including Seattle keeper Kasey Keller. “Sigi is a good coach and he’ll have them ready for us. He knows our players and he’s been to our stadium many times.”

Seattle came into the playoffs on a 10-2-3 streak during which it scored 23 goals yet struggled through its third straight postseason shutout; it lost to Houston in last year’s conference semifinals, 1-0, on aggregate.

These teams have less than two years of common history, but already they’ve infused bitterness into their matches. In August of last year, Seattle beat Los Angeles, 2-0, at HDC with goals by Montero and Zakuani in a fiercely contested match.

Beckham piled into Pete Vagenas, a former Galaxy teammate, with a studs-up tackle that earned him a red card. After the Sounders scored twice, each team lost a player; Tyrone Marshall chopped down Donovan in the 76th minute, and three minutes later, Eddie Lewis of the Galaxy conked James Riley in the head as he tried to retrieve a ball that had rolled out of play.

Schmid won’t condone a repeat of the extracurricular activities but he needs the result.