The first head-coaching job in Mel Tucker’s 23-year career began with home wins against an intrastate rival and a traditional power. He couldn’t have asked for a better honeymoon.

But since then, his Colorado Buffaloes have been racked with injuries, they’ve committed a slew of penalties and they’ve lost three of four games. The honeymoon is history, and Tucker finds himself explaining his coaching philosophy as if he were still applying for the job — still in wooing mode.

The most recent outing was the worst, a 45-3 spanking at Oregon, but Tucker said all the losses have stung.

“They’re not easy to shake off, but you have to turn the page nonetheless,” Tucker said at his weekly news conference Tuesday in Boulder, Colo. “That’s what we do. Anytime you don’t have success, if it doesn’t bother you, then something’s wrong.”

The Buffs (3-3, 1-2) are 12½-point underdogs this week against another sputtering Pac-12 team, Washington State (3-3, 0-3). Kickoff is 4 p.m. Saturday (ESPNU) at Martin Stadium in Pullman.

That betting spread might seem excessive, but Colorado’s prime weakness is its pass defense, which doesn’t augur well against WSU’s Air Raid offense, even if forecasts for rain showers prove accurate. The Buffaloes repeatedly have lost defensive backs to injuries in recent weeks and are allowing 307 passing yards per game, seventh-most in the country.

Tucker, 47, is a former Wisconsin defensive back and Nick Saban disciple who spent more than two decades as an assistant coach at high-profile Power 5 schools and NFL teams, including stints as defensive coordinator for the Bears, Jaguars and Browns.

The CU job is not only his first as a head coach but also his first in the West. It began wonderfully with wins against Colorado State and Nebraska, followed two weeks later by a road victory against Arizona State in Tucker’s Pac-12 debut. But injuries and a home loss Oct. 5 to Arizona seem to have shaken the Buffs’ confidence.

“Coaching is a challenge,” Tucker said. “It’s very competitive. You end up putting yourself out there, you put your team out there. Your resume is on the field, right? The higher you go, the more you’re exposed. To me, I like that challenge. We stumbled. Now, how are we going to get this right?”

Like Kyle Whittingham at Utah and Herm Edwards at Arizona State, Tucker is trying to parlay staunch defense and a general air of humane toughness into success in the free-wheeling Pac-12.

But at the moment, his team’s strength is its offense.

Fifth-year senior Steven Montez ranks fourth in the conference in passing yardage and boasts one of the deepest receiver crews in the league. The ace of the group is Laviska Shenault, whom some consider the prize talent of the league, and he’s mostly recovered from a core-muscle injury sustained a month ago.

But even the Buffs’ passing game unraveled last week at Eugene, Ore. Montez threw four interceptions, three of them on bobbled balls, and Colorado mustered only 299 yards of offense, some of it negated by the team’s 114 yards in penalties.

So it was back to Square 1 in Boulder this week.

“Today I told them, ‘This was a good practice — that’s what we need to do,’” Tucker said. “Now we’re going to watch the film, we’ll grade it, plus-minus everything, take it (to) the players tomorrow, then we’ll do it again. Then we’ll take this show on the road and we’ll see what happens. That’s beauty of it — no one knows what’s going to happen.

“This time next week,” he said, seemingly trying to draw reporters into the cycle of his quest, “we’ll be talking about it.”

Grummert may be contacted at daleg@lmtribune.com or (208) 816-0629.

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