sentences:  The first caution of the day flew on lap 2, after Vern Schuppan broke a joint and went off track in the first turn.The second caution flew due to a stalled car at lap 15, and the third due to debris picked up when Gordon Johncock left the pits on lap 69.After Unser was forced to make an unscheduled pit stop due to tire problems, Danny Ongais took the lead on lap 87, and held it for the next 33 laps, but soon after giving up the lead to Johncock retired with a blown engine, bringing out the final caution of the day.