The opening week of college football, really, was an anomaly.­

San Diego State lost a game it shouldn’t have lost — 40-19 at home to Eastern Illinois of the Football Championship Subdivision. Six other Football Bowl Subdivision teams lost to FCS schools they were supposed to beat.

Fresno State, coming off a heart-pounding 52-51 overtime win over Rutgers on Thursday, hosts Cal Poly on Saturday, wary of the upsets that took place over the weekend.

The Mustangs are ranked 10th nationally among FCS schools, a radar blip much brighter than Eastern Illinois, which opened the season ranked 23rd in the FCS coaches poll.

“Everyone says that the conventional wisdom is that you’re supposed to win one of these,” Fresno State coach Tim DeRuyter said. “Well, seven FBS teams thought that last weekend and seven Football Championship Subdivision teams went out and beat them in big-time stadiums.”

Cal Poly (1-0) won its season opener against the University of San Diego 38-16, plowing over the turf for 307 rushing yards with a variation of the triple option offense Fresno State prepared for against Air Force last season.

Fresno State’s defensive line knows there will be cut blocking from a team that showed its variation on Saturday. Quarterback Vince Moraga threw for 226 yards in Cal Poly’s win.

And the Bulldogs, defensive coordinator Nick Toth said, will have to adapt quickly to the Mustangs’ offense.

“We’re pretty sound versus the option,” Toth said, “but if there’s going to be something we didn’t see, we have to do a better job of adapting on the fly than we did last Thursday.”

Added defensive lineman Tyeler Davison: “It’s not an offense we go against very often, so it’s good that we have these extra days to get ready for that and prepare for the triple option and all the different things that they do.”