Power suffered a concussion and compression fractures of his second and fourth lumbar vertebrae in an accident during practice Saturday morning. He was airlifted to Memorial Hospital in Santa Rosa, Calif., where he will remain for further examination.
The accident occurred after the car driven by Nelson Phillipe spun in Turn 3. With the car sitting just over the hill in the fast, blind, downhill turn, E.J. Viso clipped the wing of Phillipe's machine before Power came down the hill and ran right into Phillipe.
Briscoe said he wished his teammate the best, but, like Castroneves, maintained his focus through qualifying.
"I'm definitely hoping Will is going to be all right," Briscoe said. "I heard he fractured his back, so it's pretty serious."
Castroneves wished Power a speedy recovery, praising him for his contribution to the team this season.
"We were all very concerned about Will and hope that he has a quick recovery," Castroneves said. "You never want to see any of your colleagues get hurt, especially a teammate. Will has done a lot to help us out this year. It's just a shame that this had to happen to him today. We all know the risks involved in racing, but that doesn't make it any easier when someone you are close to gets hurt."
Briscoe held the top qualifying position Saturday until the final minutes of the Firestone Fast Six session, when Dario Franchitti topped his lap. Still, Briscoe's effort of 1:16.8485 in the No. 6 Team Penske Dallara/Honda held up for another front-row starting position.
Briscoe, who has qualified on the front row in seven of 13 races this season, is just three points behind Scott Dixon in the IndyCar Series championship standings with four races remaining in the 2009 season. Franchitti sits third, now 19 points behind Dixon.
"We were going for it," Briscoe said. "It's really coming down to the three of us for the championship. It's been a tough one. Whoever is going to win this championship needs to go out and win races."
Castroneves, who is fourth in the standings, believed he could get more out of the No. 3 Team Penske Dallara/Honda in Saturday's qualifying.
"I'm a bit disappointed," Castroneves said. "I thought the Team Penske car was better than third place, and I'm sure Ryan feels the same way. During the first session we had a problem with our fuel pressure, which the team was able to fix for Q2 (qualifying two). Then in Q2 we had an issue with the throttle, which they were able to fix for Q3, so I guess taking all of this into consideration, we did OK. The important thing is that the car is great and I'm feeling confident going into tomorrow's race."
Power's performance this season has been a pleasant surprise for Penske Racing. In just six races, the 28-year-old Australian has one victory, two poles, four top-five finishes and has never finished outside the top 10.
Penske Racing president Tim Cindric said it was unfortunate that Power won't get a chance to compete this weekend but the team still hopes to turn in a solid performance on Sunday without their injured teammate.
"We are pulling for Will to make a quick recovery and it is so unfortunate that he won't be able to race on Sunday as he was really looking forward to getting back in the car this week," said Cindric. "Ryan and Helio did a great job in qualifying and both of the cars were quick all day so we should be in good shape for the race."
Sunday's race is scheduled to begin at 5:50 p.m. ET and will be televised live on Versus.