The College Football Playoffs semifinals are set. On Dec. 29, Alabama will face Oklahoma in the Orange Bowl and Clemson will play Notre Dame in the Cotton Bowl. Clemson is very familiar with one of the three teams in the Playoffs, having played the Crimson Tide in each of the past three postseasons.

The Tigers have less experience with the Sooners and the Fighting Irish. The last time Clemson played Oklahoma was in the 2015 Orange Bowl Playoffs semifinal, and the last time Clemson squared off against Notre Dame was on Oct. 3, 2015, in Death Valley. The good news for the Tigers – Clemson won each of those most recent meetings against Oklahoma and Notre Dame.

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However, first things first. Clemson must handle business against Notre Dame in Dallas before looking ahead to either Alabama or Oklahoma.

Here are five things you need to know about the Fighting Irish:

Solid on both sides of the ball

Notre Dame is one of six teams in the country that ranks in the top 30 nationally in both total offense and total defense. The Fighting Irish rank 28th in total offense, racking up 456 yards per game. Notre Dame ranks 21st in total defense, giving up only 331 yards per game to their opponents. The Fighting Irish do not rank in the top 10 in either category but they are solid on both sides of the ball.

Dexter Williams’ impact

Notre Dame’s starting running back, Dexter Williams, missed the first four games of the season because of suspension. However, Williams returned to the lineup against Stanford and rushed for 161 yards with a touchdown in a 38-17 win. In the eight games Williams has played, he has tallied 941 yards on just 142 carries. He leads the team with 12 rushing touchdowns.

Ian Book’s efficiency

Much like Williams, quarterback Ian Book did not play much in the first few games of the season. In the fourth game of the year at Wake Forest, coach Brian Kelly benched returning starter Brandon Wimbush and Book made the first start his career. Book passed for 325 yards with two touchdowns and added three rushing touchdowns in a 56-27 win. Book has been Notre Dame’s starter since and he has been impressive. He ranks eighth nationally in passer rating (162.50) and has thrown 19 touchdowns with just six interceptions this season. 

Lock-down corner Julian Love

One reason Notre Dame ranks in the top 30 nationally in total defense is because of their secondary, and the leader of that secondary is Julian Love. The junior cornerback is Notre Dame’s all-time leader in pass breakups and was nominated for the Nagurski Trophy and Jim Thorpe Awards this season. He has started all 12 games this season for Notre Dame, tallying 61 tackles with three tackles for loss, an interception, a QB hurry and three fumble recoveries.

Size at wide receiver   

Notre Dame’s two leading wide receivers are not only talented, but both 6-foot-4.  Senior Myles Boykin and junior Chase Claypool bring substantial size to the passing game. Boykin leads Notre Dame with 54 receptions for 803 yards with eight touchdowns. He is averaging 14.9 yards per catch. Claypool is second on the team with 48 receptions for 631 yards with four touchdowns.

Kelly Gramlich can be heard Monday-Friday 12 p.m. to 3 p.m. on “Out of Bounds” with William Qualkinbush on WCCP 105.5 The Roar. Find her on Twitter (@kellygramlich).