By ERIC OLSON AP College Football Writer

Things to watch during Week 4 of play in the Big Ten Conference:

GAME OF THE WEEK

No. 6 Ohio State (3-0) at No. 9 Notre Dame (4-0), Saturday, 6:30 p.m. CDT (NBC)

One of the most important nonconference games of the season on a day full of big games matches top-10 teams with designs on the College Football Playoff. A win here is a big step toward that goal; a loss is not insurmountable.

This is the fifth straight time since 1996 that two of college football’s biggest brands will meet while both are ranked in the top 10. The Buckeyes have won five straight in the series, including 21-10 last year in Columbus. Their last loss to the Irish was in 1936.

Notre Dame QB Sam Hartman, who already has 13 touchdown passes, will go against an Ohio State defense that has allowed a total of 20 points through three games. Buckeyes QB Kyle McCord has found a nice rhythm with six TD passes the last two weeks.

BEST MATCHUP II

No. 24 Iowa (3-0) at No. 7 Penn State (3-0), 6:40 p.m. CDT (CBS)

Penn State has scored at least 30 points in 10 straight games and is averaging 43 per game for the season. Iowa is among nine teams to have allowed three or fewer touchdowns so far.

Even if the Hawkeyes slow down Drew Allar and the Nittany Lions, it might not be enough. Iowa’s offense is ranked No. 121 nationally. Penn State’s defense has forced a Big Ten-best seven turnovers. Penn State is a 14 1/2-point favorite, according to FanDuel Sportsbook. The Hawkeyes haven’t been so big an underdog against a team other than Ohio State since 2016.

INSIDE THE NUMBERS

Purdue goes into Friday night’s meeting with Wisconsin with at least one interception in seven straight games. … Michigan goes into its home game against Rutgers second nationally in total defense (222.3 ypg) and first in scoring defense (5.3 ppg). … Rutgers is 8-31 in Big Ten road games since joining the conference in 2014, and only two of the wins have come against opponents that had winning records at the time. … Nebraska is tied for third nationally with 14 sacks, most since it had 20 at this point in 2005. The Cornhuskers had four at this point a year ago. … Illinois’ Isaiah Williams has caught a pass in 28 straight games since switching from quarterback to receiver before the 2021 season. … Maryland has won each of its first three games by at least 18 points for the first time since 1948. … Indiana goes into its game against Akron with a 12-2 record against non-Power Five opponents under Tom Allen. … Minnesota’s .603 win percentage against Northwestern is its best among Big Ten opponents the Gophers have played more than three times.

LONG SHOT

Purdue is a 5 1/2-point underdog against Wisconsin on Friday night, according to FanDuel Sportsbook. The Boilermakers haven’t beaten the Badgers in West Lafayette since 1997 and have lost 16 straight in the series. Never mind that Wisconsin picked off five passes against Georgia Southern last week. The Badgers have proved vulnerable to the pass. Purdue’s Hudson Card is coming off a 323-yard game in a loss to Syracuse and needs help from the run game.

IMPACT PLAYER

Ohio State WR Marvin Harrison Jr. can elbow his way into the Heisman Trophy conversation with another big outing against a Top 25 opponent under the lights in prime time. He’s gone over 100 yards in receptions in three of his last four games against the Top 25, including two straight. He caught six touchdowns in those four games.