Carlo Ancelotti's side have won back-to-back games after following up a 2-0 win against Malaga on Saturday with a 2-1 victory at home to Juventus on Wednesday, and the full-back feels that El Clasico has arrived at an ideal point in the season for Los Blancos.
"The match against Barcelona comes at a good time for us. We are improving and gaining confidence, so we'll see if we can win," Arbeloa told reporters.
"We know it will be a very difficult match. I'm sure that Barcelona will be at their best because they always play well against us.
"We can't look at their recent draws (against Osasuna and AC Milan) as a guide. They have a three-point lead, but in recent matches in the Camp Nou we've got good results and put in some great performances."
A win for Ancelotti's men will take them level on points with Barca at the top of La Liga.