FONTANA, Calif. (AP) Brian Vickers will be sidelined for at least three months while the NASCAR driver is taking blood thinners to treat clots in his lungs.
Before Brett Moffitt drove his No. 55 Toyota in Sunday's race at Fontana, Vickers said he still hopes to resume his racing career after his latest medical setback.
''By no means have I given up,'' Vickers said. ''I don't know what's next. I know I'm going to be on blood thinners for the next three months, and after that, I'm going to do everything I can to get back in a race car.''
Two days after blood clots were discovered in both of his lungs when Vickers alertly responded to pain by getting to a hospital, Vickers came to Auto Club Speedway to support his Michael Waltrip Racing team.
Vickers is in only minimal pain, but can't drive while taking blood thinners because his bleeding could be impossible to stop in a serious crash. He remains hopeful for good news during the summer, but Vickers also understands the reality of a racing team's needs early in a NASCAR season.
''I'll just try to figure out what makes sense with my doctors - if I can come back off of them and go racing, if there is some kind of plan that works,'' Vickers said. ''If not, then that's that. ... Am I worried? Of course. Have I given up hope? No.''
The 31-year-old Vickers has endured three bouts of blood clots and open-heart surgery in the past five years, returning to racing each time. He missed 26 races during the 2010 season after getting painful clots in his lungs and legs, followed by surgery to fix a hole in his heart.
Vickers then missed the final five races in 2013 while on blood thinners to treat a clot in his right leg.
Last December, the three-time race winner had surgery on his heart again after his body began to reject the patch. He missed the first two races of this season while his sternum healed from surgery.
He went to a hospital Friday after feeling pain in his chest following a cross-country flight - but only after pacing around his hotel room and trying to persuade himself that it hadn't happened again.
''I was still trying to convince myself it was something else,'' Vickers said. ''I did mostly listen to my own advice, which is, `Go to the doctor when you think something is wrong.'''
Vickers noted a grim serendipity in his latest setback: He is now taking the blood-thinning medication that is one of his major sponsors.
Just two days earlier, Vickers appeared with Arnold Palmer and actor Kevin Nealon at a golf tournament in Florida to promote blood clot awareness. The trio unveiled a new series of television commercials made by a pharmaceutical company.
Saturday's Xfinity Series race at Fontana was even called the Drive4Clots.com 300.
Vickers is in the final season of his contract with MWR, and he has been grateful for their unwavering support during his medical problems. Michael Waltrip has said the team hasn't made a decision about its long-term future beyond Moffitt's turn in the No. 55 car on Sunday.
''They have a team to run, and I'm probably starting to wear out their patience,'' Vickers said. ''But I know that if at all possible, they're going to stick behind me and they've proven that.''