Trailing by 17 points at half-time, the Eagles kicked four goals to one in the third quarter off the back of 17 inside 50s to six. Josh Kennedy, despite carrying an elbow injury, provided an important target with six marks and a goal.
"I think if he didn't play tonight we probably don't win," Simpson remarked.
"He is playing sore and if he falls on it the wrong way there's potential for more damage, but it is low risk.
"He doesn't need [an operation]."
Adding to his gutsy effort was the fact he dislocated his finger in the second quarter.
Simpson was also happy with his depleted backline. Without Eric Mackenzie and Mitch Brown, Jeremy McGovern and his teammates have stood up when it's mattered most.
"That last 10 minutes when we were under siege, I thought our backs really stood up as well," Simpson noted.
"[Will] Schofield's playing a key position, when I got to the club he was a running half-back/wingman.
"Hopefully we've developed more of a steely resolve.”
Simpson said he was pleased with Sharrod Wellingham (22 possessions, 11 marks, five rebound-50s), who's relishing a new role across half-back.
"He's really stepped up," Simpson said.
"He's got his last year of his contract, so he's playing with a bit more desperation than I noticed last year.
"He might be on the one-yearer's (sic) from now on."
The win moves West Coast (4-2) to second on the ladder. The Eagles’ midfield mix of experience in Matt Priddis (31 touches, 21 contested) and Mark Lecras (28 touches and a goal) and youth, Elliot Yeo and Dom Sheed, is very exciting.
Simpson insisted the club wouldn't get ahead of itself.
"We're really starting to see some excitement and development with our kids coming through," Simpson stated.
"I think we'll take a lot of confidence from this game.
"Playing our way and having the belief that it works is important for our group.
"Not getting too carried away as you can probably tell."
A struggling Gold Coast side awaits them in Perth in round seven.
We're asking all fans at the stadium to celebrate our great rivalry with Essendon! We want to take back the wave, made famous by Kevin Sheedy back in 1993. Be sure to bring your scarfs to the game and let's wave them loud and proud
00:50
SJOG Health Care Injury Update: Round 8
High Performance Manager Mathew Inness provides an update on West Coast's injured players ahead of their clash against Essendon
12:47
McGovern Press Conference 30.04.24
Senior defender Jeremy McGovern talks to the media ahead of Saturday night's home clash against the Bombers
02:21
Teaming Up With Foodbank
We've teamed up with Foodbank WA again to help West Aussies - donate today via the link below or at our home game this Saturday against Essendon. To donate please vist: https://www.foodbank.org.au/?state=wa