Kevin Harvick came into Sunday's Good Sam 500 as favourite to win, having already been victorious at Phoenix International Raceway on seven previous occasions. Sure enough he duly dominated the race and led for 139 of the 313 laps to record an eighth victory, but he had to make his way forward from 18th place on the grid which meant he didn't reach the front until lap 169, and when it finally came down to the wire his margin of victory over Carl Edwards could hardly have been tighter.

Harvick looked to have a clear run to the chequered flag in the final minutes of the NASCAR Sprint Cup Series race, when Kasey Kahne ended up in the wall in turn 4 to bring out a caution with five laps still to go. That tightened the field and set up a green-white-chequered overtime finish, with a mixture of pit stop strategies in play to make things even more interesting.

Harvick opted to maintain his track position and stayed out along with Hendrick Motorsport's Dale Earnhardt Jr. and Richard Childress Racing's Austin Dillon, while Joe Gibbs Racing's Carl Edwards, Kyle Busch and Denny Hamlin all opted to come in but take two tyres only meaning they took the restart in fourth, fifth and sixth place respectively, while others came in for a full set of four but started further back.

In the end it was clear that the two-tyre gambit had been the right one, with Earnhardt dropping to fifth place and Dillon falling to ninth by the finish. However, Harvick's performance advantage over the rest of the field was sufficient to mean that he was able to stay just ahead of the JGR tide, and when the cars cross the finish line he had managed to stay 0.01s ahead of Edwards despite some last-lap contact between the pair. That makes it the closest finish in track history, beating the previous record of 0.13s set when Ryan Newman held off Jeff Gordon in 2010.

"I knew he was better through 3 and 4," said Harvick of the moment he saw Edwards closing in his rear view mirror. "I knew I could beat him down there and I tried to protect the bottom in 3 and 4 and I just missed the bottom with all the rubber build-up on the tires and everything.

"I knew I was going to be on defence down there. I got up too high and wasn't able to stay on the bottom like I wanted to and then he got into me, like he should have, and I needed to get a good run off the corner and I was going to have to get into his door and it worked out, just barely."

"I should've wrecked him," joked Edwards. "No, those guys were doing a great job all day. They hung on with those tyres but we were faster so I thought, 'Man, I'll just move him out of the way and get by.' I just didn't move him far enough and then he got up the door and I thought 'I think he's going to beat me', so I tried to sideswipe him before he got there but I needed to be in front of his front tyre. Anyway, just a fun race.

"Man, I wish we could've won that thing," he added. "I wanted to win that thing but you win some and you lose some. It was a good race."

Hamlin managed to take third place but was left ruing the near-miss. "I thought we had a car that could win. We really did a good job back there - pit crew did a good job down the stretch there. So, overall I'm very proud of our program. We've really come a long way on this race track. Obviously this is a very pivotal race track when it comes to getting to Homestead so we want to run good here and this is a good step."

Busch claimed fourth place to continue his run of top five finishes in 2016, his best-ever start to a season. The reigning Sprint Cup champion led for the first 74 laps of the race, but the performance of the #18 started to fade shortly after the first round of pit stops. A botched pit stop on lap 165 saw him drop from third to 18th place after he overshot his marks, but he was able to fight back into the top five although worries about a tyre vibration meant he wasn't able to press his attack against the likes of Harvick and Edwards.

"We had a really good car today and we ran upfront for a bunch of the race," he said. "I'm not sure if we could've beat the #4 or not but given some different circumstances maybe.

"Overall the Skittles Camry was good. Missed it just a little bit on the long runs for sure. We just can't quite keep up as good as those guys can on the long side of the run, so that's kind of where we lost it today. I also screwed us up a little bit on pit road but we were at least able to overcome that."

Behind Earnhardt, Harvick's Stewart-Haas Racing team mate Kurt Busch finished in sixth followed by the fourth JGR car of Matt Kenseth, with Hendrick's rookie driver Chase Elliott in eighth, Dillon ninth and Wood Brothers Racing's Ryan Blaney in tenth. Jimmie Johnson and Kyle Larson narrowly missed out on the top ten.

Prior to the cliffhanger GWC finish, the race had actually seen several long uninterrupted runs. The first caution came on lap 52 when RCR's Ryan Newman hit the wall in turn 4 while his team mate Paul Menard triggered the second caution on lap 106.

"We just blew a right-front tyre," remarked Newman. of his early exit. "It must have melted the bead or something. I don't know if something failed in the cooling department or what the deal was. I didn't do anything any different than I've ever done here before. Just definitely blew a right-front tire out and that was the end of our day."

"I'm not really sure," replied Menard what had happened to the #27. "We were okay that last run. We fired off pretty decent and started getting really tight at the end. I don't know if a left-front tire blew or what going into 3. I don't know if something broke or if a tyre blew. We are going to check it out. I'm curious about it."

The next caution was triggered by Roush Fenway Racing's Ricky Stenhouse Jr. on lap 163, and Penske's Brad Keselowski blew a right rear tyre on lap 225 resulting in a debris caution on lap 226.

"We were really tight and I was having to use too much break and I think we got the tyres hot and once we did that the right front gave out from having to use too much brake," explained Stenhouse. "The cars were a handful. They were fun to drive. We just didn't quite have the Fastenal Ford dialled in like we needed to today. We were really tight, therefore we had to use too much brake"

"We ran in that tenth place range pretty much the entire race until we cut the tyre," sighed Keselowski who ended up in 29th place at the finish. "That was unfortunate and we aren't really sure why but there isn't anything we can really do about it. It is hard to say really where we would have been if that hadn't happened."

The final caution was triggered by Kahne hitting the wall with five laps to go to set up the overtime photo finish.

"We had a right front tyre go down," the Hendrick Motorsports driver commented afterwards. "It happened earlier in the race but a caution came out and I thought it was the engine at the time because of the way it kind of vibrated and changed the tone of the engine.

"We'll look at what we are doing since it happened a couple of times. We had a car capable of running in the top 15 and we were really good early. The longer the race went I felt like I got looser. I used a lot of brake during the entire the race, which I was surprised about. Yesterday in practice I didn't have to use the brake hardly at all and today with different grips I used it so much."

After the race, one of the first people to congratulate Kevin Harvick on victory lane was the car owner of the #4, Tony Stewart, who is currently still sidelined with a back injury sustained just prior to the start of the 2016 season but who has not been cleared to begin rehab and hopes to return to competition in the next few months.

It was Harvick's 32nd victory in 542 Cup races - this week marked his 500th consecutive start - and means that he now tops the championship points. Kyle Busch is tied with Harvick, but Harvick takes the official honours by virtue of his one race win. Jimmie Johnson is 14 points further back with Kurt Busch, Carl Edwards and Denny Hamlin making up the rest of the top six, four races into the new season.

The next race is the Auto Club 400 at the Auto Club Speedway in Fontana, California on Sunday March 20, after which NASCAR takes a week off for Easter before resuming at the start of April at Martinsville Speedway.

Xfinity Series: Just as was the case in Cup qualifying, Joe Gibbs Racing pulled off a 1-2-3 starting grid lock-out for the Axalta Faster Tougher Brighter 200 with Eric Jones claiming his fourth series pole ahead of team mates Daniel Suarez and Kyle Busch. By the time the chequered flag came out, it was still a JGR sweep - but Busch had succeeded in quickly rising to the top past his team mates and went on to lead for 175 of the 200 laps at Phoenix International Raceway to cross the line 2.285s ahead of Jones. It meant that Busch has won three of the first four Xfinity races of 2016, with only the season opener at Daytona having eluded him. Busch now has a record-extending 79th victories from 314 starts. Saturday afternoon's race saw three brief cautions for minor accidents for David Starr and Ray Black Jr (lap 2), Jeremy Clements (lap 58) and JJ Yeley (lap 96). In the points standings, Suarez had an eight point lead over JR Motorsports' Elliott Sadler, with Richard Childress Racing's Ty Dillon one point further back in third.

Full race results and updated Sprint Cup Championship standings.

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