In 1997 two crashes resulting in severe concussions sidelined Sharp until 1998 when he began working with the newly formed Kelley Racing team and sponsor Delphi. At Kelley, Sharp collected eight wins and four pole positions (one being at the 2001 Indianapolis 500). He was 3rd in the championship in 2001, but an influx of strong teams from CART meant that Kelley was not one of the strongest teams after that season. In 2004 he was down in 13th in the championship with a best finish of 8th — his first winless season since 1998, also ending a run of top 8 championship finishes dating back to 1998.