No Marc Bulger, no Isaac Bruce, no Torry Holt and no Mike Martz added up to no problem for the St. Louis Rams yesterday as a career-high 179 yards rushing by running back Steven Jackson led them to a 24-21 upset of the Jacksonville Jaguars.

Martz, the Rams coach who announced last week that he’d miss the remainder of the season because of a heart infection, is the architect of the high-flying offense featuring Bulger at quarterback and Bruce and Holt at receiver. If any game could usher in the changing of the guard for the St. Louis offense, this was it.

Yesterday, Jackson routinely picked up large chunks of yards running to the outside, often breaking through the grasp of Jacksonville defenders. Jacksonville’s defense plays well against runs up the middle, so the Rams sent Jackson behind offensive tackles Orlando Pace and Alex Barron, and they opened big holes for him.

Backup quarterback Jamie Martin threw three interceptions, but the Rams have their bye this week and expect a much better passing attack when Bulger, Holt, and Bruce return for their next game. At 4-4 halfway through the season, St. Louis has won two straight games and could still emerge as a worthy playoff team.

Jacksonville running back Fred Taylor, an eight-year veteran who has been bothered by an ankle injury, showed great burst and explosiveness yesterday, finishing with 165 yards and a touchdown. Second-year receiver Ernest Wilford had the best game of his career, catching six passes for 145 yards and a touchdown.

Jacksonville fell to 4-3 and is practically out of the AFC South race, where Indianapolis is 7-0 and has already won a head-to-head matchup. If Jacksonville wins a wild-card berth, it will be thanks to big games from players like Taylor and Wilford. But perhaps more importantly, it will be thanks to the schedule, which features a rematch with Indianapolis, plus eight games against teams with losing records.

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It would be easy to dismiss the Chicago Bears, who improved to 4-3 and ascended to the top of the NFC North yesterday with a 19-13 victory over Detroit, as merely the best team in a bad division. But Chicago is more than that.

After a solid first half by rookie quarterback Kyle Orton gave the Bears a lead, the impressive young Chicago defense held on as Charles Tillman returned an interception for a touchdown in overtime to seal the victory. If the Bears keep playing this well, they’ll earn their spot in the playoffs and won’t be an easy out.

Before the season, when quarterback Rex Grossman was healthy and looking to stake his claim as the Bears’ quarterback of the future, Chicago stressed the importance of developing the youngster and making steady progress. But developing a player takes a backseat to making a push for the playoffs, and Orton had his best game as a professional yesterday, completing 17 of 31 passes for 230 yards, a touchdown, and no interceptions. If the Bears are still in first place when Grossman returns from his ankle injury, it seems very unlikely that they’ll replace Orton.

Chicago’s underrated defense has several talented young players, including Tillman, middle linebacker Brian Urlacher, and end Adewale Ogunleye. But no player is more important to the Bears’ defense as tackle Ian Scott. The best defensive tackles often make an impact not by tackling the opposition themselves, but by freeing up linebackers to do it. Scott didn’t have a single tackle yesterday against Detroit, but his strength and quickness in the middle of the line forced Detroit to devote two blockers to him all day, which allowed Urlacher to finish with a game high nine tackles.

For 3-4 Detroit, blame for the loss falls in large part on quarterback Jeff Garcia, who threw the overtime interception and hasn’t looked like the wise veteran the Lions thought they were getting when they benched Joey Harrington. Garcia has wasted timeouts and taken delay of game penalties, and the Lions have scored only two touchdowns in his two games as the starter.

In the NFC North, the Lions are the only threat to the Bears’ supremacy. In a season that began with a big questions mark for the entire division, now no one wants to have to travel to Soldier Field in January.

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The Denver Broncos have been one of the NFL’s best teams in the first half of games this year, but seem to have a terrible habit of falling apart in the second half. Last week, they blew a 23-10 lead to the Giants and ended up losing 24-23. But the Broncos almost outdid themselves yesterday, jumping out to a 28-0 lead before allowing Philadelphia to crawl back to within 28-21 and drive toward a tying touchdown before Denver pulled ahead to win 49-21.

Philadelphia’s loss will lead to more questions about whether quarterback Donovan McNabb should sit out and recuperate from the sports hernia that has hobbled him for much of the season. McNabb threw incompletions on his first 12 passes and looked awkward on several early throws. He began to look more comfortable later in the game, and finished with 283 yards, but struggled with accuracy and completed only 12 of 34 passes.

McNabb and the Eagles offense were not the biggest problem, though. That honor goes to the defense. A week ago, Philadelphia used its aggressive scheme, with defensive backs lining up near the line of scrimmage, to shut down San Diego running back LaDainian Tomlinson. Yesterday, Denver showed that an effective passing attack and a good offensive line can exploit that scheme. Jake Plummer finished the day 22-of-35 for 309 yards, four touchdowns, and no interceptions, while the Broncos’ offensive line created enough creases in the Philadelphia defense that Mike Anderson and Tatum Bell each ran for more than 100 yards.

Denver is 6-2 and in first place in the AFC West, while Philadelphia fell to 4-3 with the loss. It’s a dubious time to hit the skids in Philadelphia – the Eagles now sit a game behind the first place Giants in the NFC East and play their three division rivals – the Redskins, Cowboys, and big Blue – in their next three games. If the Eagles play the next three weeks the way they played yesterday, they’ll finish last in a division they were expected to dominate.

Mr. Smith is a writer for the statistical Web site FootballOutsiders.com.