Rex or Tony? ESPN’s Skip Bayless couldn’t see a difference. The former Dallas and Chicago columnist, in a radio interview last week, called Tony Romo inconsistent and said Rex Grossman could, at any time, throw for 300 yards or several interceptions.

Rex or Tony?   ESPN’s Skip Bayless, who said Rex could throw for 300 yards at any time, and the Chicago Tribune’s David Haugh, who wondered if Rex would show Tony Romo “who the real Pro Bowler” was last year, both were undecided this week.             That was before Romo passed for 320 yards in the first three quarters alone and Grossman threw three interceptions in Dallas’ 34-10 Sunday night victory.   While Romo danced away from a fierce pass rush – “He’s very elusive. He made plays,” Grossman said – Rex fell apart. And what did the Bears say?   “Rex is my guy,” tight end Desmond Clark said.   “It’s not Rex’s fault,” defensive end Alex Brown said. “It’s everybody’s fault.”   This is the quarterback Donovan McNabb said gets picked on more than himself? No, Rex doesn’t get hammered. He gets protected. At least in his home city.   A look at Romo and Grossman shows just how far this Rex Protection Racket has gone.   Romo has the highest career passer rating (98.4) of any current NFL quarterback. Grossman (71.1) ranks 29th among current starters.   The difference becomes even larger – much larger – when it matters most. Romo’s third-down passer rating of 141.7 this year is 10 times that of Grossman’s. Romo is first in the league on third down. Rex is last.   A two-game sample is admittedly small, but this isn’t: In his last nine games, Grossman has converted only 9 of 65 third-down conversions of 5 yards or more on passing tries.   The biggest Grossman myth is the Good Rex/Bad Rex theory that Grossman needs only to erase his turnovers to be good. A myth Grossman promulgates himself. “I have to do what I do best,” he said, “make plays down field, but don’t turn the ball over.”   Third downs are just as critical. That showed again Sunday, when the Bears crossed midfield four times in the first half yet scored only 3 points against Dallas’ No. 31-rated pass defense. But that’s far from the only myth that has kept Rex shakily afloat in Chicago. Consider:   - Rex may make mistakes, but supporters say he also makes big plays. Well, Grossman ranks 25th among active starters in career yards per pass (6.56).   - At least Rex is better than the parade of mopes who have passed for passers in Chicago the last two decades. Actually, 18 times in the 21 seasons before Chicago drafted Grossman, the Bears’ leading passer had a higher passer rating than Grossman’s career 71.1. Jim Harbaugh, Steve Walsh, Eric Kramer, Shane Matthews, Jim Miller and an ancient Dave Krieg were all higher-rated Bears than Rex. Even Chad Hutchinson (73.6) topped Grossman as his injury fill-in in 2004.   - Rex isn’t a weekly threat to pass for 300 yards. He’s done so once in 31 games. In overtime vs. Tampa Bay last year. Joey Harrington and Matt Leinart have topped 400 yards as many times as Grossman has reached 300, yet no one considers them a threat to go for 400 each week.   A rare 12-yard Grossman scramble on third-and-10 briefly jump-started Chicago’s offense in the second half. Romo, though, led Dallas on 89- and 91-yard drives to take a 17-10 lead. Later, Grossman threw an interception returned for a touchdown to make it 27-10.   The Bears do have other worries. Tommie Harris (knee), Nathan Vasher (groin) and Lance Briggs (groin) left the game with injuries. Devin Hester muffed two kicks and fumbled a third. The Bears’ strengths no longer look so strong. Chicago (1-2) is two games behind Green Bay. They can’t afford Grossman to keep playing like this.   “We have to fix that,” Grossman said. “We have to make plays and not turn over the football.   “We have to start playing better. This week we will determine how we do that.”   The hard way is for Rex to improve. The easy way is for Rex to sit.   Assistant sports editor Matt Trowbridge can be reached at 815-987-1383 or