Saugatuck covered the three-mile course in 20 minutes 42.09 seconds.
Riders must hop off their bikes several times over the three-mile course, sling them over their shoulders and sprint over unbikable terrain on foot.
Today's racing conditions on the Charles River were difficult for the 4,000 competitors, who contended with gusting winds that produced slow times over the winding three-mile course.
He finished 5.4 seconds ahead of Tucker, in 18 minutes 11.67 seconds for the three-mile course.
Races on the three-mile course were timed, with crews setting off at 15-second intervals, rather than run in side-by-side competition.
In view of the distance from the city there was only a small crowd of people disposed around the three-mile course.
Harvard's junior varsity defeated Yale by 34.2 seconds, or eight boat lengths, finishing the three-mile course in 13:57.
She finished the three-mile course in 19 minutes 26.32 seconds, defeating Kristin Goodrich of the United States national team by 4.16 seconds.
Racing conditions were ideal for Saturday's first events, with hardly a ripple on the three-mile course.
The jockeys clutch the reins as the horses gallop heavily along the three-mile course.