The best NFL running backs can change direction in a blink.
But this is the kind of directional change that would have a coach swallowing his whistle: Buffalo's LeSean McCoy is the only one of last season's top 10 rushers who currently ranks among this year's top 10, and he's hobbling around on a bum knee.
Remember how 2014 rushing champion DeMarco Murray was going to tear it up in Philadelphia? He's been a bust.
Seattle's Marshawn Lynch is hurt and hasn't played since mid-November, and long since done for the season are Pittsburgh's Le'Veon Bell and Houston's Arian Foster.
There was some buzz before the season about Frank Gore going from San Francisco to Indianapolis. For a 32-year-old back — ancient for that position — he's done a respectable job, but doesn't have a 100-yard rushing game this season and has scored once since Week 6.
The backs who figure to make headlines in the coming weeks are ones such as Arizona rookie David Johnson, a third-round pick from Northern Iowa, who has run for 378 yards in December (more than 24 teams); Charcandrick West, an unlikely hero who has stepped in for the injured Jamaal Charles in Kansas City, which has won eight in a row; and the combination of Christine Michael and Bryce Brown, who figure to share the load in Seattle in the absence of Lynch and now-injured rookie standout Thomas Rawls.
Sometimes, filling the void at running back requires creative thinking. The AFC's hottest team, New England, reached into the where-are-they-now file this week and signed Steven Jackson, 32, who had eight consecutive 1,000-yard seasons in St. Louis before signing with Atlanta in 2013. The past two seasons, he ran for 543 and 707 yards.
Dion Lewis and LeGarrette Blount are on injured reserve for the Patriots, who last week promoted rookie Joey Iosefa from the practice squad to help at the position. That led to the Tuesday signing of Jackson, who called it an early Christmas gift.
Quarterback Tom Brady, whose team has a history of reinvigorating onetime stars at the end of their careers, said he's looking forward to having Jackson in the backfield.
"I've always watched from afar and seen how tremendous a player he is, what kind of professional he is, so it's great to have players like that," Brady told reporters. "Hopefully, he can add a lot to our team, and we'll see."
Jackson could pan out. Considering the way running backs go up and down in their productivity, changing directions in a blink, stranger things have happened.
The third time's a charm for Pittsburgh kicker Chris Boswell, who has found a home with the Steelers after getting cut by the Houston Texans in their 2014 training camp, then by the New York Giants last summer.
Boswell has emerged as one of the NFL's hottest kickers, making 26 of 28 field goals (including two of two from beyond 50 yards), and is on pace for the best season by a kicker in club history.
As kicking stories go, Pittsburgh's season started like a sad country song. The team lost Shaun Suisham to a torn ACL in the first exhibition game, signed Garrett Hartley, who is now on injured reserve, then traded a sixth-round pick to Jacksonville for Josh Scobee.
Scobee was a disaster from the start, missing two kicks in the opener at New England, then missing two more in a 23-20 loss to Baltimore in early October. The Steelers released him after that and signed Boswell.
"I always believed that my time would come," Boswell told the Pittsburgh Post-Gazette this week. "It was just a matter of what I did with my opportunity when it came."
Seattle receiver Doug Baldwin, slowed by a bad hamstring, is listed as questionable for Sunday's game against St. Louis. He participated fully in practice Friday.
In recent weeks, Baldwin has left opposing defenses hamstrung, scoring 10 touchdowns in the last four games. The only receiver to have matched that over a four-game span is Jerry Rice.
Baldwin has had at least two touchdown receptions in each of the last four games. Cris Carter and Calvin Johnson are the only other NFL players to have multiple touchdown catches in four consecutive games.
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