For the 2007 season Hornish again returned to Penske, starting the Indianapolis 500 in fifth place. Running consistently in the top ten, he finished fourth when the race was halted by rain after 166 laps. Hornish's only win of the season was the Bombardier Learjet 550 at Texas Motor Speedway, when he started in second place and led for 159 of its 228 laps. His series-best finish on a road course or street circuit, second place at the Camping World Watkins Glen Grand Prix, was overshadowed by an altercation with Tony Kanaan. With the season-ending race at Chicagoland, Hornish ended his IndyCar career with a third-place finish (after starting second and leading for a race-high 90 laps) and finished fifth in the points standings.