France's Hubert Robert on Pequignet Littlemaille and New Jersey's Michaela Murphy on Gusty Monroe shared a victory in the $12,500 International Open Jumper Puissance at the Washington International Horse Show at Capital Centre last night, with an unsuccessful attempt at breaking the world record.

Each entry to successfully clear each fence continues the competition. The puissance wall is raised four times or until there is a winner.

All nine riders survived the first round, clearing all five fences and the 5-foot-9 wall. But, after two scratches, only seven advanced to attempt the 6-6 wall.

One horse refused the wall at that height and two others withdrew after clear rounds to send the other four to attempt the obstacle raised to 7 feet. Robert, Murphy and Norman Dello Joio on Stranger returned to jump at 7-3 1/4; only Robert and Murphy made it.

Both riders failed at 7-8 3/4, an attempt at breaking the world indoor record of 7-7 1/2 set in 1983 by Anthony D'Ambrosio on Sweet 'N Low.

As a rookie last year, Chris Kappler's best performance was a second place finish on Concorde in the Cincinnati Grand Prix. He had only two other ribbon finishes. This week at the Washington International Horse Show, the St. Charles, Ill., native has won two intermediate jumper events with the Dutch-bred Warrent to gain the championship with 10 points.

Many of the top U.S. riders compete in the daily jumper events. Kappler defeated the field of 24 Monday to win the $2,000 event in 34.4 seconds.

In Thursday's $7,500 Range Rover Open Jumper competition, Kappler and Concorde shared first place with Mario Deslauriers and Box Car Willie after each finished in 34.33.

The victories gave Kappler the best showing in intermediate jumper events. Michael Matz of Collegeville, Pa., and Lynsaya received reserve champion honors with eight points.

Matz rode to victory in yesterday's $3,500 Jumper Stake in 25.38. Rodney Jenkins was second.