Without Grabavoy, RSL scored road wins over Chivas (4-0) and the L.A. Galaxy (2-1). The victories solidified Real's position in the Western Conference playoff race.
"Obviously the guys did great getting two results," Grabavoy said. "So that probably makes it a little easier not to rush my situation."
Coach Jason Kreis hopes Grabavoy, who has started 21 of 25 matches this season, will play.
"Ned has been a really, really important player for us all season," Kreis said. "To have him as an option, whether that's starting or off the bench, would be terrific.
"If he starts the game, he does all the little things that help us from minute 1. If he comes onto a game, he has the creative ideas to help us if we need a goal."
Even if Grabavoy returns, RSL will be shorthanded against Seattle.
Kyle Beckerman (United States), Nick Rimando (United States), Alvaro Saborio (Costa Rica) and Will Johnson (Canada) are currently playing for their national teams in World Cup qualifying.
"We are going to approach it as if they're not going to be available," Kreis said. "Plain and simple."
Costa Rica plays at home Tuesday night. Meanwhile, Canada plays at Honduras.
"I don't see any way Sabo or Will Johnson will be available," Kreis said. "That's too much travel after having matches the night before our game. We wouldn't even ask them to get to Seattle. Both of them are 100 percent out."
The U.S. national team plays Guatemala on Tuesday night in Kansas City, which could also eliminate Beckerman and Rimando from playing against the Sounders.
"It's a very difficult task to get from Kansas City to Seattle," Kreis said, "and to travel on the same day as a game is not ideal. So we'll prepare like they won't be available."
Another RSL player, Luis Gil, is with the United States' under-20 national team in Spain.
Real Salt Lake at Seattle
P Wednesday, 9 p.m.
TV • NBCSN
Radio • 700 AM, 1600 AM