Cinzano, a 7-year-old bay gelding ridden by owner Randy Rouse, captured his fourth straight timber race yesterday, leading start to end in the Potomac Cup Challenge Trophy at Potomac's Belvedere Farm before a crowd of 8,000.

Cinzano won the race, which is a leg of the Seven Corners Challenge Trophy competition, with a time of 5 minutes 1 1/5 seconds. Gentleman Pro was second and St. Denis finished third.

Rider Dan Yovanovich, pressed into double duty, rode Land Landing and Mona Hill home first in the divisions of the split $1,000 Potomac Plate Challenge Trophy steeplechase.

Yovanovich of Upperville, Va., pushed Land Landing to the front of a six-horse field for the last mile of the three-mile timber race and won it in 6:05 2/5.

Baltic Baron, with Grant Schneidman aboard, trailed by 12 lengths in second; Sara Myst, ridden by Speedy Smithwick, was third.

A decisive wire-to-wire victory on Mona Hill over the same 19-fence course in the second division let Yovanovich, 29, build the first riding points in the four-part Maryland Governor's Cup competition.

Mona Hill was clocked at 6:06 1/5, easily beating Mr. Jam, with Liz McKnight up. Third was Squarely Rich, with owner Doug Worrall in the saddle.

Yovanovich earlier in the day had ridden Bright Answer home first in the $1,500 General H. H. Semmes Challenge Trophy, a 1 3/4-mile hurdle event.