PULLMAN — The beauty in John Mateer, Washington State’s burgeoning quarterback, is in how much room he has to grow. He’s still only a redshirt sophomore, all of 20 years old, and in his first year at the controls, coaches are still figuring out how to make the most of him.

Is he best throwing deep balls? Not yet. Can he make plays scrambling from the pocket? Some, but not all. Can he make quick and accurate passes closer to the line of scrimmage? Without a doubt.

The best thing Mateer showed in WSU’s 42-10 win over Hawaii on Saturday, though, was that he’s willing to accept all of that. He stayed within himself, kept things simple and didn’t try to evade a thousand tackles on scrambles. He let his receivers make catches and rack up yards after the catch, which they’ve shown they’re some of the best in the country at.

Above all, Mateer seemed to understand that for as much potential as he has, he has work to do to reach it. For a guy of his experience — in his first year starting, playing just his seventh game as the guy for the Cougs — that speaks volumes. In his most mature game of his career, Mateer looked happy to simplify his game, taking things as they come, not forcing them.

Mateer completed 23 of 27 passes for 295 yards and three touchdowns. For the first time this season against an FBS foe, he didn’t throw an interception. Some of the best plays he made were the easiest: Two designed QB keepers for touchdowns. A quick throw over the middle to receiver Carlos Hernandez, who took it to the house. A flip to speedy wideout Kris Hutson, who zoomed into the end zone from short distance, and a laser of a touchdown pass to tight end Cooper Mathers.

That was no coincidence. Headed into this game, WSU coach Jake Dickert said, coaches “narrowed the menu down a little bit, to things he’s really confident in.” They couldn’t afford for Mateer to replicate his last outing, a 17-for-34, two-turnover effort in a win over Fresno State last weekend.

In that one, Mateer tried to do a little too much. He lost one fumble scrambling around the field, trying to avoid a sack. He threw one interception into the end zone, the second straight game he did so, and his accuracy eluded him. As the Bulldogs dropped more defenders in coverage and tried to force him into becoming a pocket passer, it was clear Mateer was a little uncomfortable.

So credit WSU coaches for adjusting: They amplified Mateer’s strengths by putting him in positions to use them. They didn’t ask him to throw deep, which he’s struggled with. Instead, they wanted Mateer to be himself, and right now that means simplifying the game for him.

“We’re still discovering what all his strengths are as he continues to get more games underneath his belt,” Dickert said. “But I think when you look back at the whole game, I felt John was really confident. I thought he was really controlled. You don’t remember all those wild scramble plays that we’ve had probably the last couple weeks. That’s a good job by the offensive line.”

Let’s be clear about this, too: It’s no knock on Mateer to acknowledge he’s best when things are simple. Playing quarterback at this level is hard, even for veterans, let alone first-year starters. On Saturday night alone, Alabama quarterback and Heisman Trophy candidate Jalen Milroe tossed two picks in a loss to Tennessee. Clemson QB Cade Klubnik tossed an interception against an overmatched Virginia team.

Heck, remember last season? Remember when defenses realized that former WSU QB Cam Ward wasn’t much of a threat to run — that his offense wasn’t as a whole — and sat back in coverage, picking him off several times that way? That was his fourth season of college football, and he was vulnerable.

The more games you play, the more teams have film to watch and weaknesses to exploit, which is part of Mateer’s situation. He may have only made seven starts so far, but that’s a lot of snaps — 265 dropbacks to be exact — and a lot of chances for defenses to study you. After this Hawaii game, it’s clear opposing defenses would rather Mateer eschew his running abilities and become a pocket passer, which is not his forte.

He’s put several holes in his game on tape. At times, he’ll fail to look off safeties, which is why he threw a pick against Fresno State. At others, he’ll fail to see them entirely, which is why he threw his interception against Boise State last month. Still other times, he’ll try to use his great gift of athleticism a touch too much, trying to make plays that aren’t there.

That much defenses are keying in on. The good news for Mateer is that his coaches are, too, which is where this simplified gameplan comes in. Many of his best plays came on RPOs, run-pass options, which gave him a chance to hand the ball off if he didn’t like what he saw downfield. For Mateer, simple decisions like those led to the best results.

“They were giving us space. They were often soft and inside on the corners,” Mateer said, “and then in the RPO game, it was just there. And we trusted our guys. We told our receivers, block, block, block on the quick RPOs, and they did, and it was great. It was working. That was the emphasis this week, and so I took it, and it worked.”

Even the chances Mateer took worked out. He only threw a handful of deep passes, which was on purpose, but he unfurled one early in the third quarter, after a turnover. He dropped back, looked for senior receiver Kyle Williams on the left side and unleashed a nearly-perfect throw.

A little underthrown, sure, but Williams is the Cougars’ best receiver, and there’s a level of trust Mateer is rightfully putting in Williams in spots like those.

It’s clear Mateer wants to trust himself to make all kinds of plays, but it’s also clear he understands he’s not there yet. Quarterbacks with that kind of maturity don’t grow on trees. Quarterbacks with the ability to leverage it in game situations are even rarer, and as the Cougs embark on a chunk of schedule seemingly lighter on competition, Mateer is on the right track.

A simpler track.