RENTON — Garry Gilliam’s greeting to a familiar face inside the visiting locker room at the University of Minnesota was a question. Actually, it was a proclamation.

“What’s you think of THAT?!” the Seahawks right tackle bellowed last weekend following Seattle’s 38-7 steamrolling over the NFC North-leading Vikings.

His coaches think the world of what Gilliam and his rebounding offensive line have done over the last three games. The Seahawks (7-5) have beaten San Francisco plus playoff contenders Pittsburgh and Minnesota by averaging 35 points and 456 yards per game. Russell Wilson has completed 77 percent of his passes with 11 touchdowns, no interceptions, plus his first rushing touchdown of the season. It’s the best three-game stretch of his career.

Seattle’s probability of reaching the postseason has gone from 23 percent when it was 4-5 last month to 83 percent entering Sunday’s game at Baltimore (4-8), according to the sports analytics group numberFire.

All this is largely because of the large men that block for Wilson.

“The biggest thing is, we are developing as a group. Everybody is pulling the same way,” veteran line coach Tom Cable said Sunday inside the door of the Seahawks’ happy locker room in Minneapolis. “We talked about this (Saturday) night: If we’re just the best us, that’s good enough. So don’t strain. Don’t stress. Don’t do all that other nonsense. Just relax and play football. I think we are doing that.”

Until now, they were ruining the season.

Cable said in August he thought this line that began the season with starters in three new positions could be the most athletic and potentially best one he’s had in five Seattle seasons. Eyes rolled. Center Drew Nowak — the first choice to replace Max Unger after the team traded the two-time Pro Bowl center to New Orleans for tight end Jimmy Graham — was a college defensive tackle. Nowak had zero NFL starts. New starting left guard Justin Britt was the inconsistent starting right tackle last season as a rookie. Gilliam, the new right tackle, was a tight end for three seasons at Penn State.

Starting with September’s opener in St. Louis deep into October, defenses blitzed Seattle’s new line incessantly — and rarely with much resistance. Wilson got sacked 31 times in seven games. Seattle was 3-4.

“Early in the year we would target, target — and then on the other side this guy was coming free,” Cable said. “You look at it and go, ‘Wait a minute. We aren’t on the same page.”

Critics blamed the Seahawks’ entire philosophy of how they have put together offensive lines recently: Signing undrafted free agents or, in the case of their center, those waived by other teams or were on others’ practice squads.

It seemed like an experiment, cobbling together a line out of minimum-salary players. And it seemed to be failing.

Yet Cable kept saying he was seeing progress.

“Yeah,” he said Sunday with a grin, “but nobody believes that.

“Every day you look at little things that are happening and you see them put that together and put that together, and pretty soon it starts to grow.

“It’s pretty cool.”

As Cable kept preaching patience and progress, head coach Pete Carroll says now he kept believing. Carroll trusted his veteran assistant would turn these blockers with mostly scant experience into a serviceable and perhaps even excelling line.

It was a fulcrum of faith upon which Seattle’s entire season tipped.

“When given the opportunity to connect with Tom to get him to come here (in January 2011, after two seasons as head coach of the Oakland Raiders), it was because my draw to Tom was his commitment and his background in the zone-running game,” Carroll said. “I knew what his history was and how he grew up with the coaches that mentored him, and I’ve watched him coach on the practice field and saw the results of the years that he’s had in the past. All the variety of things that he’s done demonstrated to me a great commitment. So my job was to put him in a position where he could be really successful, I thought.

“Because to me it’s so important that we know who we are and what we are in all phases of our game. And in the running game in particular I think it’s huge.

“So I have absolute trust.”

Carroll and Cable, a 27-year veteran of college and NFL line coaching starting at Idaho in 1987, game plan each week many of the plays coordinator Darrell Bevell calls. Cable has the title of assistant head coach, but he essentially is the running-game coordinator.

“We do a lot of stuff together in this,” Carroll said. “That’s one of my favorite parts of coaching on our team is the stuff that Tom and I get to do together, and decide how we’re going with the trends and the changes, and how we want to adjust and stuff like that. But he has absolutely my trust in anything.”

After these last three games, Cable looks like a sage. He replaced Nowak with Patrick Lewis at center after five games. Lewis, Britt, Gilliam, left tackle Russell Okung and right guard J.R. Sweezy are suddenly as big a reason the Seahawks are showing signs of another late-season rampage as they were for the 2-4 and 4-5 starts.

The line that couldn’t sustain drives has been 24 for 40 (60 percent) converting third downs. The line that couldn’t drive defenders into the end zone is doing that now — literally; Seattle has scored eight times in 10 red-zone trips.

On second-and-goal from the Vikings 4 last weekend, away from the cut left by rookie runner Thomas Rawls, Sweezy drove Vikings leading tackler Chad Greenway 5 yards, across the goal line, and put the linebacker on his back in the end zone.

Since Lewis has replaced Nowak, Cable explained, Seattle’s had the right blockers on the right defenders. Plus, Wilson has quickly gotten the pass off to the area from where blitzes have come.

As is his way, Cable doesn’t profess much personal satisfaction in his linemen’s improvement.

“I always care about the players. So to me, for them, I’m happy for the guys,” he said. “I’ve been through this a million times. For them, I’m pleased, because they are doing it.”

Finally.

Asked if his trust wavered at all during the darkness of 0-2, 2-4 and 4-5 this season, Carroll shook his head.

“No, no,” the head man said. “We had to fix what was going on in the protection game. We had to fix that and we had to help ourselves some. We thought we might come along a little faster than we did, so we made some moves and some decisions that helped us that basically had to do with making sure that the ball was out of the quarterback’s hand, and to help those guys get settled in. And they’ve done a great job of adjusting to that.

“It’s been a big, big change for us. … It’s probably the single most significant change that’s happened during the course of the year.”