Tom Dienhart, BTN.com Senior Writer, June 26, 2013

It's time to consider Week 13 in my early week-by-week analysis of the 2013 Big Ten football season. This is a busy week, with all 12 teams in action, and it's one that figures to feature games that impact the Legends and Leaders championship races. Get all the storylines, matchups and my game rankings for Week 13 in this post.

[ MORE: Week 1 | Week 2 | Week 3 | Week 4 | Week 5 | Week 6 | Week 7 | Week 8 | Week 9 | Week 10 | Week 11 | Week 12 ]

Game of the week: Michigan State at Northwestern. Many feel this could be one of Northwestern?s best teams ever. That makes MSU?s trip to Evanston a key Legends Division game. The Spartans lost last year, 23-20, to the Wildcats in East Lansing. Before that, Michigan State had won four in a row vs. NU. It last lost two in a row to Northwestern in 2000-2001.

Ranking Week 13 games
1. Michigan State at Northwestern
2. Nebraska at Penn State
3. Michigan at Iowa
4. Wisconsin at Minnesota
5. Illinois at Purdue
6. Indiana at Ohio State

Quarterback matchup to watch: It won?t be on many radars, but the battle between Tre Roberson (the likely Indiana starter) and Ohio State?s Braxton Miller could be a gem. Each is among the most athletic signal-callers in the Big Ten. And each is a better thrower than advertised. Who will make the big plays? And avoid the big mistake?

Coordinator matchup to watch: Michigan State defensive coordinator Pat Narduzzi vs. Northwestern offensive coordinator Mick McCall. Narduzzi?s talented crew will be pushed by a diverse and talented Wildcats? offense. Lots of interesting matchups to watch, including the Spartan linebackers vs. NU running back Venric Mark-and shifty quarterback Kain Colter.

Upset alert: Going to Penn State will be tough for Nebraska, but the Nittany Lions may be worn down and beaten up by then. Still, Penn State figures to be a tough out. The front-line players are among the best in the league. And few squads are better coached than the Nittany Lions. And games like this are de facto bowl games for a Penn State club that can?t go bowling because of NCAA probation.

Storylines: All 12 teams are in action, which is rare. In fact, it happens just six times in 14 weeks. ? Nebraska has won three in a row and four of the last five meetings with Penn State. ? Minnesota has lost nine in a row to Wisconsin and is just 4-18 vs. the Badgers since 1991 in the battle for Paul Bunyan?s Axe. ? Iowa beat Michigan three times in a row before falling last season in Ann Arbor, 42-17. So, the Hawkeyes don?t fear the Wolverines. In fact, Iowa is 3-1 vs. Michigan in the last four meetings in Iowa City. And, by the time these teams meet in Iowa City, Iowa may have a whole lot on the line. Or maybe not. ? Purdue and Illinois battle for the Cannon. And, the Boilermakers have ruled by winning 10 of the last 13 meetings after the Fighting Illini had won six in a row. ? The Ohio State-Indiana series is the definition of ?lopsided.? Since the Hoosiers won in 1951, the Buckeyes are 49-2-2 vs. the Hoosiers. The two wins were in 1987-88 and the two ties were in 1959 and 1990.

About Tom Dienhart BTN.com senior writer Tom Dienhart is a veteran sports journalist who covers Big Ten football and men's basketball for BTN.com and BTN TV. Find him on Twitter and Facebook, read all of his work at btn.com/tomdienhart, and subscribe to his posts via RSS. Also, send questions to his weekly mailbag using the form below and read all of his previous answers in his reader mailbag section.

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