BATON ROUGE, La. -- Quarterback Danny Etling completed 19 of 30 passes for 215 yards, including a 37-yard touchdown strike to D.J. Chark, and Leonard Fournette scored his first two touchdowns of the season as No. 20 LSU held off a furious fourth-quarter rally for a 23-20 victory over Mississippi State on Saturday night at Tiger Stadium.

LSU raced to a 23-3 halftime lead and held Mississippi State to one field goal, a 37-yarder by Westin Graves, in the first 26 minutes of the second half to lead 23-6.

But after Fournette's second fumble of the game, the Bulldogs caught fire behind backup quarterback Damian Williams. Mississippi State scored two touchdowns in 40 seconds -- a 1-yard keeper by Williams and a 4-yard yard quick out to Fred Ross -- to close the gap to 23-20 with 3:30 left.

The second touchdown came after Mississippi State recovered an onside kick at the LSU 32 and Williams hit Ross for 28 yards to the LSU 4.

Then, after LSU went three-and-out, the Bulldogs had one more chance. On third down from the Mississippi State 25, Key forced an incompletion. On fourth-and-8, Key raced in from the blindside to sack Williams, ending the game.

Fournette rushed for 147 yards on 28 carries but fumbled twice. His final fumble was critical because it stopped an LSU drive that moved the ball from its 1-yard line to Mississippi State 33, setting up the Bulldogs' comeback.

With Etling at the controls, LSU's offense looked transformed from the one that had sputtered through the first five quarters of the season.

It wasn't only that the junior transfer from Purdue completed 14 of 20 passes for 172 yards in the first half. Etling also kept the chains moving, converting 6 of 10 third downs in the first half as LSU raced to a 23-3 lead.

The Tigers had converted only 43 percent of their third downs in the first two games.

After resting his sore ankle in last week's 34-13 win over Jacksonville State, Fournette looked quick, sharp and powerful. He showed his brute force on a 5-yard score in the first quarter and then displayed his speed on a 25-yard dash around left tackle on a quick pitch.

LSU's other touchdown of the half came on a perfect 37-yard post pattern, with Etling hitting wide receiver D.J. Chark in the back of the end zone. Etling's best throw of the game had come a few plays earlier when he stood tall in the face of a blitz and threw a 15-yard out pattern to Malachi Dupre to pick up a third-and-9.

Mississippi State's only points of the half came on Westin Graves' 41-yard field goal. LSU's Colby Delahoussaye matched that with a 27-yard field goal to cap a 68-yard drive just before halftime to stretch the Tigers' lead to 20 points.

LSU outgained Mississippi State 282-80 in the first half and held a 16-5 edge in first downs.

NOTES: LSU DE Arden Key had two sacks, including the final one of QB Damian Williams, that sealed the game with 1:30 left. ... Four LSU offensive linemen sustained injuries and two did not return – T Toby Weatherby (right ankle) and T K.J. Malone (hamstring). ... Mississippi State coach Dan Mullen nearly changed the game when he inserted QB Damian Williams in the final six minutes. Williams, a junior from Archbishop Rummel High School in Metairie, La., completed 5 of 8 passes for 94 yards. He threw and ran for one TD each.