New Zealand cyclist Glen Chadwick survived the toughest day of the Tour of Mexico to hold on to the overall lead with three stages remaining.
The 146.3km fifth stage from Zamora to Morelia included three categorised climbs, which shattered the 140-strong field and saw only 35 riders together
at the finish in Morelia.
Jose Benites (Scott-American Beef) won the sprint over Ivan Fanelli (Cinelli-OPD) and Ignazio Sarabia (Extremadura).
Team Type 1 kept Chadwick in the yellow jersey, getting him to the finish unscathed despite the loss of Matt Wilson to illness.
"The boys were under attack immediately and although Matt started, we knew we didn't have him today and there would be a good chance he would not finish," Team Type 1 sport director Ed Beamon said.
Over the first climb, a four-man break slipped off the front, but Team Type 1 kept the gap within five minutes.
Three more riders bridged the gap to the leaders on the second climb, but Chadwick's lead stayed safe.
The torrid pace ripped apart what was left of the field and hauled back all but one of the seven leaders.
The main field, now reduced to about three dozen, regrouped on the fast descent after the final climb.
Chadwick, who competed in the Beijing Olympics road race, has held the yellow jersey since the second day of the eight-stage, 1206km race.
He has an overall time of 16 hours, 36 minutes, just two seconds ahead of Mexican Archimedes Lam (Tecos UAG) and six ahead of Spain's Gonzalo Zambrano (Extremadura).
The 150km sixth stage is from Morelia to Zitacuaro.
- NZPA
