Leaders Barca will go four points clear at top with victory
Second-placed Real Madrid cut gap to one point with victory over Elche on Saturday
Sevilla go into game 14th in table, looking for first win in three
Joan Garcia gets down low to deny Ruben Vargas.
He was pushed as he took the shot and appeals for a penalty but the referee is not interested.
The resulting corner is easily caught by Garcia.
Raphinha takes a Barcelona corner and Ronald Araujo heads over from close range.
He should have done much better with that.
Barcelona make a triple change.
On: Ronald Araujo, Marc Casado and Lamine Yamal.
Off: Joao Cancelo, Ronny Bardghji and Marc Bernal.
Joao Cancelo's direct running into the box led to the first penalty for Barcelona and now he has a goal of his own.
He joined the club on loan for the second time in January and he has been hugely influential in this game.
Joao Cancelo drives into the box, cuts inside while sending Nemanja Gudelj and stabs the ball towards goal where it goes in off the post.
A great finish.
Joao CanceloImage source, Getty Images
Joao Cancelo
Raphinha now has 11 La Liga goals for the season, level with Robert Lewandowski.
Top scorer Lamine Yamal (14 goals) is on the bench.
Raphinha has his hat-trick!
Fermin Lopez drives at the Sevilla defence and passes to Raphinha.
He turns and shoots and his shot deflects off Nemanja Gudelj before flying past Odysseas Vlachodimos in the Sevilla goal.
Raphinha
Raphinha
On: Chidera Ejuke, Ruben Vargas and Neal Maupay.
Off: Jose Carmona, Gabriel Suazo and Akor Adams.
Barcelona have scored 35 first-half goals in 28 games, more than any other team in La Liga this season.
That was Oso's first La Liga goal this season.
It was a good time to get it as Sevilla barely posed a threat for the majority of the first half.
The whistle blows as Barcelona concede a goal on the stroke of half time.
Sevilla have a goal back.
Juanlu Sanchez crosses into the box and Oso hooks a shot into the bottom corner.
One shot on target, one goal.
Dani Olmo charges forward and swings a teasing ball into the box.
It goes over Raphinha but finds Robert Lewandowski whose header is off target.
Speaking of Dani Olmo, he has made it 3-0 to Barcelona.
A cross comes into the box and he ghost in behind the Sevilla defence to slot home from close range.
Dani Olmo
Dani Olmo
Raphinha scored a hat-trick as La Liga leaders Barcelona easily beat struggling Sevilla.
The Brazilian chipped in the first of two penalties in the ninth minute after Joao Cancelo had been fouled by Djibril Sow.
Raphinha's second spot-kick, awarded by the video assistant referee (VAR) following Jose Angel Carmona's handball to stop Cancelo, was slotted into the bottom corner 12 minutes later.
Dani Olmo looked to have made the game safe at Spotify Camp Nou with a tidy first-time finish from 16 yards.
But Oso's cushioned volley, his first goal in senior football, gave Sevilla hope just before the break.
However, Hansi Flick's side continued their dominance to wrap things up in the second half.
First, Raphinha's shot was heavily deflected by Nemanja Gudelj and looped into the top corner six minutes after the restart.
Cancelo then ran from the halfway line before firing in their fifth on the hour mark.
Seconds before the end, Sow headed in a consolation from Oso's cross.
Barcelona are four points ahead of Real Madrid with 10 games to go, while Sevilla are 14th, only five points above the relegation zone.
Raphinha was replaced in the 82nd minute, to a standing ovation, by Gavi - making his first appearance since August after a serious knee injury.
The Catalans, in between their two Champions League last-16 ties with Newcastle, also brought on Lamine Yamal as a second-half substitute.
Barca are at home to Eddie Howe's men in the second leg on Wednesday (17:45 GMT), having drawn 1-1 on Tyneside last week.