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LSU linebacker Damone Clark (18) makes the tackle on Mississippi State quarterback K.J. Costello (3) for an incomplete pass in the first half of the Tigers' home opener against Mississippi State during the coronavirus pandemic, Saturday, September 26, 2020, in Baton Rouge, La. Mississippi State was penalized for intentional grounding on the play.

Mississippi State's KJ Costello has only played one game in the Southeastern Conference, but that's all it took to rewrite a line in the record book that not even Joe Burrow managed to touch.

The Bulldogs quarterback -- a transfer from Stanford -- completed 36 of his 60 passes on Saturday for 623 yards in a 44-34 victory, decimating the record for opponent passing yardage in Tiger Stadium by nearly two lengths of the field.

“Without a doubt, the SEC, it means more," Costello said after the game. "I can’t say anything else but that.”

In the past 20 years up through Saturday afternoon, the Tigers hadn't allowed a single passer to eclipse even the 500-yard mark in any game. LSU did allow one 500-yard passing game in a 2006 loss to the Florida Gators, but starter Rex Grossman accounted for only 464 of those yards. Grossman's performance had stood as the most yards by an opponent in Tiger Stadium history.

Tommy Hodson still holds the LSU record for yardage at Tiger Stadium with his 438-yard performance against Tennessee in 1989. Burrow surpassed that total four times in 2019, but none came at home -- and the final two came in the College Football Playoff Semifinals and Championship games.

Costello bested the overall SEC record by 79 yards, which had stood since 1993 and the 544-yard performance by Georgia's Eric Zeier against Southern Miss.

LSU's Rohan Davey is tied for No. 3 on that same list with Kentucky's Jared Lorenzen. That 528-yard performance by Davey against Alabama in 2001 remains the program's single-game yardage record, one of the few Burrow didn't topple on his 2019 championship run.

Costello's performance was good for No. 10 all time in FBS history.

Burrow's successor Myles Brennan put up big overall numbers in the losing effort, completing 27 of 46 passes for 345 yards and three touchdowns to go with two interceptions.

But the game belonged to Mississippi State, which took full advantage of a defense without All-American cornerback Derek Stingley Jr. The sophomore missed the 2020 opener due to an illness, according to the team.

LSU allowed 400-plus yards passing in just five other games over the past two decades, the most recent coming to Texas' Sam Ehlinger during an LSU win in the 2019 season.

Check out first-half highlights from LSU's opener at Tiger Stadium against Mississippi State

Email Jeff Nowak at jnowak@theadvocate.com

Twitter: @Jeff_Nowak