Manteca High’s Guss Schmiedt Field was a sloppy, slippery mess Friday, and the cold wind made for even harsher conditions.

A Favorable setting for the physical Buffaloes, one would think, with the athletic Wolf Pack of Cosumnes Oaks visiting for a first-round contest in the Sac-Joaquin Section Division-III playoffs.

“We have a (artificial) turf field, so these are hard conditions for us,” Cosumnes Oaks quarterback Andrew Williams admitted.

It appeared to have been lined up perfectly for the third-seeded Buffs, but it was they who struggled with the elements.

Plagued by five turnovers, Manteca suffered yet another stunning opening-round loss, 14-0. That’s three straight one-and-outs in as many years, all at the hands of lower-seeded teams.

“It’s definitely painful,” said Manteca coach Eric Reis. “Our expectations are to win these games and for whatever reason we didn’t get it done tonight.”

The whole thing was a new experience for Elk Grove-based Cosumnes Oaks (8-3), seeded 14th in its first postseason appearance.

“For a four-year program, this was a big victory for us,” Williams said. “I feel like they kind of put us a little too low. I mean, 14 seed, I thought we deserved something higher than that. But they put at the 14 seed and we played a good, tough No. 3 seed and we came out with the victory.”

Quarterback Alex Martinez (7 of 15, 44 yards) threw two interceptions and lost two fumbles. At one point he had six straight incompletions — an overall uncharacteristic effort for a player who made few mistakes at the beginning of the season before a thumb injury sidelined him for two-plus games.

“I just wasn’t executing like I know I could,” Martinez said. “(Conditions) weren’t really a factor — no excuses. You still have to come out and do your thing, and we didn’t do it tonight.”

Williams, meanwhile, did his thing for Cosumnes Oaks, even if the muddy surface took away the Pack’s advantage in speed.

The shifty signal caller, who operates out of the spread, scored on a 5-yard run up the middle early in the second quarter for the game’s first points. Cosumnes linebacker Etewafi Levi intercepted a pass and returned it to the Manteca 28 to set up the scoring drive.

Williams was in on two more big plays that put Manteca (9-2) away in the fourth. The first was a short toss to a wide-open Dylan Griffith, who stretched the catch-and-run play 68 yards for a touchdown and a 14-0 lead with 9:11 to go.

On the previous drive, Manteca plowed its way to the 20 and had a chance to keep the drive alive on second-and-1. Hoping to catch Cosumnes Oaks off guard, the Buffaloes opted to take a shot in the end zone, but Martinez’s pass was picked off by Boise State-commit Marcus Rios, who out-jumped Manteca standout receiver Eric Ceja. That was the first of two interceptions for Rios on the night.

“I thought that was our chance,” Reis said. “I thought they’d overplay the run, but to their credit they played way back and their guy went up and got the ball. Eric Ceja has made those plays all year, and unfortunately their guy got it over him.”

Manteca was still in the ballgame on its next series, which started at the Wolf Pack 35 thanks to Ceja’s 29-yard kickoff return. The Buffs again turned it over in the red zone, as Williams sacked Martinez, forced a fumble and recovered it himself.

Offensively, Williams had only thrown for 16 yards until the 68-yard connection with Griffith, and he finished six of nine with 84 yards while scampering for 42 on 15 rushing attempts.

Manteca otherwise played well defensively, yielding just nine first downs and 215 total yards. On offense, the Buffaloes racked up 210 yards and 18 first downs.

“With five turnovers we can’t beat anybody,” Reis said. “I thought defensively we played real, real well tonight. We kept ourselves in the game against some pretty special athletes on that side of the field, but when you give up five turnovers you don’t give yourself a chance.”

Back-up QB Ryan Fox gave the Buffalo hopeful a nice glimpse into the future. He played the final four minutes behind center and completed seven of nine for 73 yards.

Despite his team’s impressive record this season, Reis said expectations are higher for next year with players like Fox returning with valuable game experience under their belts.

“This was an absolute rebuilding year; we had two starters back from last year,” Reis said. “If you told me at the beginning of the year we’d go 9-2 I’d say, ‘Absolutely, I’ll take it.’ Realistically, I thought we’d go 6-4.”