The last lap began with James Toseland in fifth, ahead of fellow rookie Andrea Dovizioso, with Capirossi and Kawasaki's John Hopkins in close pursuit.
As the four fanned-out across the track for a 'do or die' attack into the 90-degree final left hander, Toseland and Dovizioso bumped each other wide, prompting Capirossi to throw his Suzuki inside them both - while Hopkins then blasted past an off-line Dovizioso to snatch seventh place, behind Toseland, on the exit of the turn.
At the chequered flag, all four were covered by just 0.9 of a second.
"I started really aggressive because I knew the Bridgestone tyres would work well at the beginning and I tried to stay with top guys, but as the tyre started to wear I had to defend my position," smiled Loris, whose fifth place marked Suzuki's best MotoGP finish at Jerez since the introduction of the four-stroke regulations. "In the last couple of laps I fought with Toseland and Dovizioso, but I beat both of them in the last corner. That was for sure nice for me!"
Toseland had been battling bronchitis all weekend, but still sliced mercilessly forward during an exciting charge up the order from tenth place at the end of lap one.
"I really had to dig deep in that race," said Toseland of his physical condition. "At one point it looked like I might not be able to ride so to finish sixth is a great result. What I was worried about was if I couldn't breath properly then that might have made me dizzy in the race but luckily I was fine.
"The bike felt great and the front Michelin tyre worked great. That's why I was able to pass all the guys at the same place coming onto the back straight. I was getting good drive off the corner but I still couldn't get side by side on the straights to line them up for a pass on the brakes. It would have been do-or-die on the brakes, but because my front tyre was so good it really hooked well mid-corner round turn five onto the back straight and my corner speed carried me underneath Vermeulen, Dovizioso and Capirossi.
"I was disappointed not to keep fifth, especially after I'd battled so hard for it. The last corner was a bit manic and I don't know how Andrea stayed on the track because he was in there so hot. I got a bit pushed out and Loris came up the inside.
"To finish sixth like in Qatar and back that result up on a track I've never raced at in my condition is really good for me. This bike and this team are capable of being in the top six, even with a touch of bronchitis. I'm looking forward to getting the new engine now. We are one of the few that can actually look forward to getting something new for the next race and I can't wait for the new engine," he concluded.
After an early mistake, Hopkins had been ninth for much of the race, then overtook former team-mate Chris Vermeulen with eight laps to go - and was in the right place at the right time during the final turn chaos.