Brian Kelly continues to add pieces to his staff with the latest being Jamar Cain, the former Oklahoma defensive line coach.

Cain, who was set to follow Lincoln Riley from Oklahoma to USC and even changed his Twitter picture to him in a USC shirt, will be the new defensive line coach and run game coordinator in Baton Rouge.

Pete Thamel of Yahoo Sports broke the news first.

Cain spent the past two seasons at OU and helped the Sooners rank third and first in the Big 12 in sacks. He had previous stops at Arizona State (2019), Fresno State (2017-18), North Dakota State (2014-16) and Wyoming (2013). Cain also served as a defensive graduate assistant at Ohio in 2005 on a Bobcats defense coordinated by Jimmy Burrow.

LSU officially named Matt House as the team's new defensive coordinator and added Robert Steeples as a defensive coach earlier this week.

Here's his bio from the Oklahoma team site:

-- Hired in January 2020 as Oklahoma’s outside linebackers and defensive ends coach after serving the 2019 season as Arizona State’s defensive line coach. He was Fresno State’s defensive line coach during the 2017-18 seasons and spent the 2014-16 campaigns at FCS powerhouse North Dakota State overseeing defensive ends.

-- His 2020 unit propelled OU to top-25 national rankings in interceptions (3rd at 16), opponent third-down conversion percentage (4th at 27.9), sacks per game (7th at 3.4), rushing defense (9th at 105.1 ypg), pass efficiency defense (9th at 112.9), opponent yards per rush (19th at 3.5) and tackles for loss per game (22nd at 7.4).

-- Pupil Nik Bonitto (outside linebacker) ranked 13th in the country in 2020 with his 8.0 sacks (in 10 games) while Ronnie Perkins (defensive end and third-round NFL Draft pick) had 5.5 sacks (in six games). Bonitto and Perkins, who were both second-team All-Big 12 honorees, tied for second on the squad with 10.5 tackles for loss (for a combined 76 yards).

-- Coached for a 2019 Arizona State team that finished 8-5 and had six takeaways in a 20-14 Sun Bowl win over Florida State.

-- With Cain on staff, ASU's 2019 run defense was significantly better than the year before he arrived. It ranked 26th nationally in 2019 by allowing 125.1 rushing yards per game, and 24th by permitting 3.5 yards per carry. In 2018, before he was on staff, ASU ranked 74th and 66th, respectively, at 170.5 and 4.3.

-- His defensive line was one of the elements that helped Fresno State compile a 22-6 record over the 2017 and 2018 seasons. The Bulldogs earned a spot in the Mountain West Championship Game both years and upset No. 16 Boise State 19-16 in the 2018 edition. Fresno also won the 2017 Hawai’i Bowl (beat Houston 33-27) and the 2018 Las Vegas Bowl (beat Arizona State 31-20).

-- A year before his arrival at Fresno State, the Bulldogs ranked 83rd in the country by allowing 30.9 points per game. Each of the following two seasons, with Cain on board, they ranked in the top 10 nationally in scoring defense, culminating in a 2018 campaign in which they finished third in the country by allowing only 14.1 points per game. Notably, after Fresno finished with the 123rd-ranked rushing defense (247.4 ypg) in 2016, the Bulldogs ranked 11th in 2017 (113.4 ypg) and 30th in 2018 (132.1 ypg).

-- 2018 first-team All-Mountain West defensive end Mykal Walker enjoyed a breakout junior campaign as part of Cain’s Fresno State defensive line, recording 67 tackles (33 solo) and ranking second in the league in tackles per game (5.6) among linemen.

-- In his first season in Fresno, Cain successfully converted outside linebacker Tobenna Okeke into a second-team All-MWC selection at defensive end after he picked up 11 sacks in 2017.

-- During his three seasons at North Dakota State, the Bison compiled a 40-5 record and captured the 2014 and 2015 FCS National Championships.

-- Coached several impact players while at NDSU, including 2014 Buck Buchanan Award winner Kyle Emanuel, who was recognized as the best defensive player in the FCS. The consensus All-American had 32.5 tackles for loss and 19.5 sacks his senior year and the San Diego Chargers selected him with their fifth-round pick. Cain also was responsible for the development of FCS All-America defensive end Greg Menard, who was nominated for the 2016 Buck Buchanan Award.• Spent the 2013 season at Wyoming, serving as defensive line coach and later as interim defensive coordinator.

-- Got his first full-time coaching opportunities as a defensive line assistant at the FCS level, beginning at Missouri State (2006-08; defensive ends) and Cal Poly (2009-12; defensive line).

-- Participated in the NFL's minority internship in the summer of 2008 (Arizona Cardinals) and in 2009 (Kansas City Chiefs).

-- Spent two seasons as a high school coach and one as an assistant coach at Sacramento City College before getting his opportunity at the FBS level as a defensive graduate assistant in 2005 at Ohio University under head coach Frank Solich. His responsibilities at Ohio were with the defensive ends.

Accomplishments as a Player

-- Started collegiate playing career at Sacramento City College where he was a first-team all-state selection as a defensive lineman.

-- Played his final two seasons at New Mexico State and was a 2002 second-team All-Sun Belt Conference pick as a senior.