LANDOVER, MD. — They didn't lose for Luck, and they didn't win with Ponder. Slugging their way to a victory that mattered only in the hearts and minds of those wearing purple, the Vikings on Saturday eradicated the possibility of drafting Stanford quarterback Andrew Luck while introducing an unexpected challenger to the slippery throne upon which all of their recent quarterbacks have squirmed.

Saturday, Christian Ponder again looked shaky in the pocket, and then on the second play of the second half he took a vicious hit. He left the game because of a concussion. One play earlier, star running back Adrian Peterson had left because of a severe knee injury.

When Joe Webb entered, the Vikings trailed 13-10 to a Washington team that had held the Giants to 10 points a week earlier. Webb faced the same limitations that had plagued Ponder -- a shaky offensive line and a shallow receiving corps. Now he lacked Peterson, as well.

In the last 25 minutes, Webb produced a comeback victory and altered the Vikings' most essential debate. He ran for one touchdown and threw for two more. He not only led the Vikings to a 33-26 victory, he ensured that Luck won't be quarterbacking the Vikings next year but still raised the possibility that Ponder could be holding a clipboard.

I asked Vikings coach Leslie Frazier whether Webb has earned a shot at starting.

"That's a good one," Frazier said. "Because of some of the things he does, and what it does for the rest of the team, you can't ignore him. It's something you're going to have to take a real hard look at going forward. He's done it. He did it a season ago, as you recall."

We all tend to overreact to quarterbacks who win games, which is why Tim Tebow could become our nation's most debated sports celebrity while he was bouncing more passes than Ricky Rubio. What's important to remember is that the same NFL experts who shape public opinion on quarterbacks also make a lot of mistakes, which explains Ryan Leaf, JaMarcus Russell, Heath Shuler and Akili Smith. Those guys probably looked great during draft workouts.

Webb has looked great in his past two NFL games, while playing under pressure and with a flawed offense. In limited time over the past two seasons, Webb has produced the Vikings' most impressive victory, last year at Philadelphia; their most impressive comeback, two weeks ago at Detroit; and their most clutch performance, Saturday against the Redskins.

Saturday, he produced touchdowns on his first three possessions. When he produced a field goal on his fourth, he had led seven consecutive drives that ended inside the opponents' 10.

Webb has a powerful arm. He can throw with touch, as he did on a 17-yard touchdown pass to Kyle Rudolph. He avoids mistakes, having thrown no interceptions and having taken only two sacks this season. He rallies his teammates. And he is one of the most dynamic runners we've ever seen play quarterback.

Webb has not built an extensive enough résumé for the Vikings to give up on Ponder. But given a fair playing field the past three weeks, Webb has excelled while Ponder has failed.

"When we need him, he comes through," said tight end Visanthe Shiancoe. "He's got a track record now. As a quarterback, he's extraordinary. I think he's definitely a starting quarterback in this league, put in the right position."

Every team wants to build around a pocket passer, but Webb is most comparable, in build and talent, to Cam Newton. Remember, there were accomplished talent evaluators questioning Cam Newton even after he won a national title and a Heisman; now he's the most dynamic player and promising quarterback in the NFL.

This league is always slow to change ... until someone has success with a new idea. Then everyone copies it. Webb could be a better version of Tebow, and a less-polished version of Newton.

"If you're ever around Joe, his personality is so outgoing and infectious, he's always in a good mood, so guys expect something to happen when he goes in," Frazier said. "Some guys just have that."

I don't know if Webb will be an outstanding NFL quarterback. The thing is, the Vikings don't know either, and they won't unless they give their most dynamic quarterback the long look he has earned.

Jim Souhan can be heard Sundays from 10 a.m. to noon and weekdays at 2 p.m. on 1500ESPN. His Twitter name is SouhanStrib. • jsouhan@startribune.com