We all know that Real Madrid is more favored than Chelsea but that doesn't mean they're superior either, because Real Madrid's performance has seen a decline lately so I think Chelsea still has a chance to get a ticket to the next round (even though it's not as big as the opportunities that Real Madrid has). I guess both teams will definitely be equally determined to win because it could be that the Champions League is the only way for them to get a trophy (especially for Chelsea who are clearly out of the Premier League title race).
Actually Real Madrid is more favored team than Chelsea in quarter final due consistent performance in Champion League and domestic league than Chelsea have loss top fourth standing position in Primer League. But Graham Potter success made comeback second leg on 16th round after winning two goals from Dortmund with first leg losing one goals. But Real Madrid difference than Dortmund and how new strategy from Potter needed to stop Real Madrid in quarter final.