The Brit will no doubt point to errors earlier in the season for his failure to retain his crown, his first having been won with Andretti Green Racing last season. He and Hornish ended the year tied on 475 points, but the American's four-win tally was double that of his rival which handed him the title, his third after two clinched with Panther Racing in 2001 and 2002.
Penske team-mate Helio Castroneves finished the season third just two points adrift, but saw his championship ambitions disappear with fourth on the road in Chicago, while Dixon finished fourth overall having had the most to do heading into the finale.
Hornish's title is a first for Penske in the IRL, the team having bounced back to the front of the field following its switch to Honda engines in 2006. Ganassi also switched from rival Toyota as the series went 'one make' and the pair dominated throughout, dividing the spoils up between them season-long.
“This is about as excited as I've ever been,” a jubilant Hornish enthused afterwards. “It's been a great day for us and a great year. I wanted to win the race real bad, but I couldn't take too many chances out there.
“The season couldn't have gone much better for me. Winning the Indianapolis 500 was the highlight of my career, but this is right up there.”
“It was a clean race, with lots of good racing,” added team chief Roger Penske, whose outfit has won 14 Indy 500 titles in the past. “It's been a long year and a great season. We came over to the IRL to support the Indianapolis 500, and I'm glad we could win the championship. It was one we didn't have, and when you don't have something you really want it.”
Wheldon was magnanimous in defeat, the reigning champion admitting he had endured too much of a troubled season to ultimately lift the crown.
“All credit goes to Roger Penske and Sam,” he said. “We've had a somewhat difficult and frustrating year and this is perhaps a bittersweet end.
