Deep down inside, is Robby Gordon a better open-wheel or stock-car driver?

If this Sunday is any indication, the same argument that has bounced back and forth throughout his career could potentially and finally be answered when Gordon tries to win his first Indianapolis 500, and then goes for double or nothing in the Coca-Cola 600 later the same day.

Gordon arguably has his best chance ever at winning the 500, starting on the outside of the front row in his eighth career start at Indianapolis Motor Speedway. Several hours later, after missing the morning drivers' meeting to drive Indy, he'll start at the rear of the 600 field, in a car that qualifed 38th Friday for Winston Cup's longest and most grueling race.

	Robby Gordon is splitting his time once again between Charlotte and Indianapolis in his quest to win two of the sport's biggest races.

Gordon is participating in his fourth so-called "double," namely running Indy in the late morning/early afternoon, then hopping on a plane to suburban Charlotte to climb into his No. 31 Chevrolet for the late afternoon/evening 600 under the lights at Lowe's Motor Speedway.

"I think I'm physically ready for it," Gordon said. "Mentally, I believe I'm ready for it, as well.

"The '600' is more physically demanding than the Indy 500, even though the Indy cars don't have power steering like Winston Cup cars. Indy cars don't generate the heat and high temperatures we have in Winston Cup cars. Indy is often a mental game and the way I drive those cars is I kind of sit back in my chair and go for the ride. You can't manhandle those cars or you'll be in the wall quicker than you can imagine. You can't yank on the wheel up in Indy like you can do with these cars."

While this is his fourth shot at fully completing the day-night doubleheader, Gordon has only been able to finish the entire 1,100-mile journey on two of the most famous racetracks in the country just once. Gordon finished eighth last year at Indianapolis, followed by a 16th-place showing at Charlotte. Due to a weather delays, he was unable to complete the "double" in its entirety in 1997, when rain forced the 500 to be run the following day. Likewise in 2000, rain delayed the start of the 500, forcing Gordon to start late in the 600 after the race had already begun, thus negating the opportunity to fully run both ends of each race.

But now the scene is set for Gordon to win both races - weather permitting, of course. And even if he doesn't take the checkered flag at either place, he's still shooting to beat Tony Stewart's all-time "double" record of two years ago, when the defending Winston Cup champ finished sixth at Indianapolis and third at Charlotte.

Not only is he doing his regular job for Richard Childress Racing at Charlotte, Gordon has perhaps the best open-wheel car he's ever driven in his career at Indy, courtesy of former open-wheel rival Michael Andretti.

That Gordon was able to put the Andretti-owned car on the outside of the front row says a lot. That Andretti let his former on-track foe drive it says even more. Of course, the business relationship between Gordon's Cingular Wireless sponsorship in Winston Cup and Andretti's link to Motorola in the Indy Racing League also had a lot to do with what Andretti calls "a natural synergy" of letting Gordon drive for him.

"Why did we hire Robby to drive one of our cars? Well, first, we think he can do the job," Andretti said. "We wanted to have somebody that could be competitive. The second thing, and the real clincher for him, is that Cingular is a big customer of Motorola. So, that relationship is very important and that really helped seal it for him."

Gordon has come extremely close to winning at Indianapolis, albeit in a non-double year. He was leading the race in 1999 on the next-to-last lap before running out of fuel short of the finish line, ultimately finishing a disappointing fourth.

"I have been very close to winning the Indy 500 several times and it's been pretty heartbreaking each time when it didn't happen," said Gordon, who has five career top-10 finishes at the famous Brickyard. "I was a little bummed when we ran out of gas in 1999, but at the same time we had positioned ourselves to lead the Indy 500 and proved we were a force to be reckoned with.

"At least three times, possibly five times, we've given away the win in the Indy 500. We've made decisions or mistakes that have cost us ending up in Victory Lane. If I had won the Indy 500 just one of those times, my career would be a little bit different right now. I could walk into sponsor meetings as an Indy 500 winner and there are not too many other drivers who can say that.

"I have had so many opportunities to be competitive and I have let then slip away time and again. Now that I'm 34, I have learned from my past mistakes and I am a smarter race-car driver than I was before."

Gordon has been called a natural Indy-car driver and an acquired stock-car driver in his career, meaning he and his talent fit Indy-car racing like a glove, but that his quest for success in Winston Cup has been both a lengthy learning process and hard work trying to succeed in a racing genre that does not have as natural a feel to him as driving an open-wheel car does.

Despite the fact that he's running full-time for Richard Childress Racing, historically one of the best teams in Winston Cup, Gordon has been repeatedly asked this past month whether winning at Indianapolis -- known as the biggest race in the world -- or at Charlotte would have more meaning to him as a driver.

"Winning the Indianapolis 500 has been a lifelong dream of mine and I've come pretty close," Gordon said. "It would be like winning the Daytona 500, and this year we finished sixth in that race, won the 125 qualifying race, and were in a position to win the Daytona 500.

"I'd like to win the Indy 500 over the Coca-Cola 600, but I'd also like to take those points from winning the 600 and put them in the bank just as easily because I want to prove everyone wrong, especially the naysayers, who said I would never fit into Winston Cup. My goal is to finish in the top 10 and we're not too far off from that.

"I feel like I have grown up and matured concerning what it takes to finish races and we're going to do everything we can, even while running the Indy 500, to make sure the No. 31 team has a shot at the Winston Cup championship, and to score points week-in and week-out."

But as daunting as Sunday's schedule is for Gordon -- driving completely different race cars that perform totally different, and with the completely opposite G-forces and drafting forces he'll have to contend with -- Gordon's biggest problem may very well be off the racetrack rather than on it.

Namely, fatigue.

Last year, Gordon went against the advice of doctors and refused to have an intravenous solution inserted into his arm during the flight from Indianapolis to Charlotte. The IV was intended to replenish his body fluids and electrolytes lost competing in the 500. And while he felt fine during the flight and the first part of the 600, by the end of the night, he was in pain with a severe stomach cramp -- a valuable lesson learned that he won't repeat this year.

He need look no further than Stewart's finish in the 2001 "double" -- Stewart was barely able to climb out of his Pontiac at Charlotte, took a couple of steps and collapsed on pit road from exhaustion, forcing doctors to quickly give him oxygen and an IV to replenish his lost fluids, not to mention the 10 pounds Stewart lost that day. And that, despite having IV and liquid intake on the flight between Indianapolis and Charlotte.

"I'll be honest, I didn't do a whole lot to train for the 'double' last year, but I wasn't tired at the end of the 600," Gordon admitted. "I did get a cramp in my stomach under my left rib section that I didn't expect. I'm sure that was because of the g-forces and dehydration. I didn't take the IV between the Indy 500 and the Coca-Cola 600 because I felt so good after Indy and had so much adrenaline running. I felt fine and I refused it but I'll take it this year. But since I had those cramps at Charlotte, I started rehydration, which is like a salt solution drink that I drink before a race that helps keep water in my body.

"I'm in good enough shape and eating well, that with the addition of the IV, I don't foresee a problem like I had last year. I was just terribly cramped up for about the last 200 or 300 miles of the race in the 600 last year, and I learned my lesson."

Gordon compares the "double" to racing the Baja 1000, although that grueling off-road event is a non-stop 1,000 mile jaunt that does not include the nearly three hour break Gordon will have between Indy and Charlotte.

Yet, Gordon will approach Sunday's twin-bill in almost the same exact fashion he has in the past when he's competed at Baja: the two most important things will be patience and pacing.

"I think the biggest thing is the understanding that you have to finish to finish first," Gordon said. "I think it's Winston Cup that teaches me to be consistent and to finish races. Going into the Indy 500 and Coca-Cola 600, I have to finish the Indy 500. If I'm to win, I have to finish it. I can't take any unnecessary risks. It's the same with the Coca-Cola 600, you can't use it up early. You've got to be good at the end."

Known on the Winston Cup circuit as the "other Gordon" or the "anti-Jeff," Robby Gordon heads into Sunday with a realistic chance to stand out above the crowd and do something that no other driver, not even Jeff -- no relation, please -- has ever done on Memorial Day: win both the Indianapolis 500 and the Coca-Cola 600.

It won't be easy, but Robby is ready.

"I honestly feel that with the right luck, I can win the 500, and with the Winston Cup team we've got in Charlotte, who knows what I can do in the 600, as well. I'm going to try and make the most of it."

Jerry Bonkowski covers NASCAR for ESPN.com. He can be reached at Motorsportwriter@Yahoo.com.