The following is the fifth of eight position reviews of the Bears' 2018 season.

A strong performance by the offensive line helped lead the Bears to a 12-4 record and their first NFC North championship since 2010.

The unit helped the Bears score at least 24 points in 11 games, their most since they also tallied at least 24 points 11 times in 1995. The offense allowed only 33 sacks, tied for the eighth fewest in the NFL, and ranked 11th in rushing with 121.1 yards per game.

The line excelled under the direction of coach Harry Hiestand, who returned for a second stint with the Bears in 2018 after spending the previous six years in the same role at Notre Dame. Hiestand previously was the Bears' offensive line coach from 2005-09 on Lovie Smith's staff, helping the team win two NFC North titles and reach Super Bowl XLI.

"Harry has done an unbelievable job," said center Cody Whitehair. "With Harry, it's just consistent coaching and teaching of techniques. Later in the year as your body gets worn down, you tend to slip on your techniques. He's constantly on us about that and I think that's what's contributed to a lot of our success."

The line in 2018 was led by Whitehair and left tackle Charles Leno Jr., who became the first Bears offensive linemates to be named to the Pro Bowl together since center Olin Kreutz and guard Ruben Brown in 2006, the last year the Bears reached the Super Bowl.

Since the Bears chose Whitehair in the second round of the 2016 draft out of Kansas State, he has started all 16 games at center in each of his three seasons. In 2018, he was the only Bears player on offense or defense to play every single snap.

Leno has appeared in 70 games with 62 starts since being selected by the Bears in the seventh round of the 2014 draft out of Boise State. Since joining the No. 1 offense in Week 4 of the 2015 season, Leno has not missed a game, making 61 straight starts.

Right guard Kyle Long started the first seven games in 2018 before injuring his foot Nov. 4 in Buffalo. He missed eight contests before returning to start the Bears' regular-season finale in Minnesota and the wild-card playoff game against the Eagles.

Bryan Witzmann, a four-year NFL veteran who was signed by the Bears Oct. 18, made seven starts in Long's place. Witzmann played for the Chiefs in 2016-17 when Bears coach Matt Nagy was Kansas City's offensive coordinator.

"I feel fortunate that we were able to pick him up when we did," general manager Ryan Pace said during an appearance on the Bears pregame radio show prior to the regular-season finale. "His knowledge of the offense, that was important. We could just put him right in, and he's done a great job, and I think he's a true pro just the way he approaches everything, and again, we're fortunate to have him."

The Bears showed how they feel about right tackle Bobby Massie Jan. 26 when they signed him to a four-year contract extension through 2022. Massie has started 46 of 48 games in three seasons with the Bears, including all 16 contests in 2018.

"Bobby has been an important part of our offensive line the past three years and has shown steady improvement during that time," Pace said. "Bobby has a tremendous work ethic and has displayed the kind of toughness and consistency we want in our players. More importantly, he is a great teammate and we're excited to keep him in the fold."

Veteran Eric Kush started the first six games at left guard before yielding to rookie second-round pick James Daniels, who opened the final 10 contests.

Reserve offensive lineman Bradley Sowell showed his versatility on offense in 2018, lining up as an extra tight end and fullback. The 6-7, 312-pounder caught a 2-yard touchdown pass from Mitchell Trubisky Dec. 9 in a 15-6 win over the Rams on a gadget play that was dubbed "Santa's Sleigh." 

"We needed a play, so they gave it to the playmaker I guess," Sowell joked after the game. "It was neat. It was one of those things that I'm glad coach Nagy trusts me to do."