Los Blancos' lead over Barcelona in the Liga table has shrunken to four points following this weekend's results, and Arbeloa has stressed that Madrid have to return to winning ways in the next few games.
"We always think we're going to win our games, but there is a lot at stake for all teams right now and Valencia gave a good performance," said Arbeloa to reporters.
"We're aware of how many games we have to play in the season. We would have settled for having a four-point lead right now at the start of the campaign.
"We have to do our best to win every match, starting with the ones against Atletico Madrid and Sporting. We have to win on Wednesday, but Atletico are a strong side that's changed a lot with [Diego] Simeone."
Wednesday's match at the Vicente Calderon kicks off at 22.00CET.
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