There's pressure on RSL (16-11-8), too, to handle such a large lead. Should Seattle (18-8-9) win 3-0, the game would go into a 30-minute overtime, then, if needed, penalty kicks.
"We need to approach this game as we would any other game," RSL coach Jason Kreis said. "It might be just [coach] speak, but for me we've got to approach it as if we're 0-0 or maybe 1-0.
"We've been in this situation a lot of times. Our players know what is expected of them."
Nothing can be taken for granted. RSL has lost three 3-0 or 4-1 games in the past five weeks, including twice on the road.
Consequently, it didn't take too long for the euphoria of the first leg to fade away before third-seeded Real began to mentally prepare for game two against the No. 2 seed Sounders.
"Soon as the whistle blew I was ready," RSL midfielder Kyle Beckerman said. "It didn't feel like the end of the game, it felt like halftime. All of our guys were on the same page, nobody was celebrating.
"It felt good to give a good performance in front of our great fans, but we all knew there was a lot more work to be done."
RSL came prepared defensively in the first leg. For the first time in 77 league and playoff matches Seattle failed to generate a single shot on goal.
Meanwhile, Real outshot the Sounders, 19-10, including 12 shots on goal. Alvaro Saborio scored twice and Ned Grabavoy added a third goal. The offensive explosion as well as the 90-minute effort appeared as if by magic, given that RSL had not won in its last six regular season games.
"I was very concerned entering the playoffs with so many negative results in a row," Kreis said. "It spelled a little bit of gloom and doom for me."
However, he added, "The guys have an innate belief in themselves … and we did see some signs of that the weekend before against Portland."
RSL finished the season with two consecutive draws, including 1-1 against Portland in Rio Tinto Stadium, a game RSL dominated for much of the match.
Real Salt Lake does enter Wednesday's game with question marks in the back. Center backs Nat Borchers and Jamison Olave are listed as questionable with thigh injuries.
This is especially concerning, considering what RSL expects from Seattle.
"It's tough, those are two huge players for us," RSL goalkeeper Nick Rimando said. "Who knows what is going to happen come Wednesday, but we've got to keep our heads in the game."
RSL must also look to counterattack when possible. It would be difficult to play strictly defense for 90 minutes and hope for a positive result.
"We're not going to bunker in at all," Beckerman said. "We're going to try and be the better team like we were Saturday. There will be time when we'll have to weather the storm … But we're going to try and dictate the game and score some goals."
Real Salt Lake at Seattle Sounders FC
P At CenturyLink Field, Seattle
Kickoff • Wednesday, 8 p.m.
TV • ESPN2. Radio • 700 AM/1600 AM
Records • Seattle 18-8-9, RSL 16-11-8
Series record • RSL leads, 3-2-2
Last meeting, RSL 3-0 (Oct. 29)
About the Sounders • Seattle has scored just one goal in its five total playoff games. … Midfielder Mauro Rosales remains questionable after suffering a knee injury in the season finale against Chivas USA.
About RSL • Defenders Nat Borchers and Jamison Olave are questionable with strained quad muscles. … RSL defeated Seattle at CenturyLink Field in September, 2-1. … Defender Tony Beltran appears fit and ready to play for the first time in six weeks.