Barcelona midfielder Rafinha expects Celtic to be out for revenge when the sides meet at Parkhead on Wednesday.
Luis Enrique's men began their Champions League Group C campaign with a resounding 7-0 win over the Scottish Premiership winners at Camp Nou in September, with Lionel Messi hitting a hat-trick.
Celtic have produced improved displays in the competition since, taking a point apiece off Manchester City and Borussia Monchengladbach, and Rafinha expects to see more evidence of this as Barca chase the victory that will guarantee their progress to the knockout stages.
"It's going to be complicated," he told a pre-match news conference. "They will want to show their worth and it's going to be a hard game.
"It really is an important game, especially after the weekend. In LaLiga, of course we want to be as close as possible to Real Madrid."
Rafinha was referring to the setback of a goalless draw at home to Malaga in Spain's top flight that leaves Barcelona four points behind bitter rivals Madrid at the summit.
Messi sat out that match through illness, while Luis Suarez was suspended.
As Barca aim to bounce back from that blow, along with a 3-1 loss at City last time out in this competition, having the feted 'MSN' combination back in attack will be an undeniable boost in Rafinha's opinion.
"[Messi] is better, he trained with us yesterday," Rafinha said. "We don't depend only on him and we hope he can play.
"For me they are the best three players, the best forwards in the world and it's great to have them at our disposal."
On Barcelona's present form, Rafinha added: "We're not at all worried.
"Not beating Malaga - it wasn't because we didn't try; it was just one of those games where the ball wouldn't go in."
