Rangers need to win at the Benito Villamarin Stadium on Thursday night to confirm a place in the knockout rounds of the Europa League.
A win in Seville would also guarantee them top spot in the group and a direct entry into the last 16 of the competition.
Rangers did beat Betis at Ibrox earlier in the group stage, but Pellegrini stressed that his side were the better team on that night and the Gers team are very different now as well.
He insisted that Clement’s team are completely different as the Belgian’s experience of playing in European competition is evident in the way Rangers play.
The Betis boss also pointed out that the Rangers boss always goes out for a win and his team need to be focused in order to get a result.
Pellegrini said in a press conference: “In Glasgow, we played well and dominated much of the game.
“This is a different Rangers; they changed their coach and they are not playing the same way.
“He is used to international tournaments and we will have to play well.
“He always goes out to win games, even more so now as the draw won’t work for him.
“We will have to be focused and be the Betis we have always been.”
Celtic are already out of Europe and the onus is now on Rangers to keep Scotland’s flag flying on the continent.
