Passage: In the track events, the best cyclist was Frenchman Paul Masson, who won the one lap time trial, the sprint event, and the 10,000 meters. In the 100 kilometres event, Masson entered as a pacemaker for his compatriot Léon Flameng. Flameng won the event, after a fall, and after stopping to wait for his Greek opponent Georgios Kolettis to fix a mechanical problem. The Austrian fencer Adolf Schmal won the 12-hour race, which was completed by only two cyclists, while the road race event was won by Aristidis Konstantinidis.

Question: What did Masson enter the 100 km event as?
pacemaker