Actually you’re not, People display bias when they gather or remember information selectively, or when they interpret it in a biased way. Therefore you are only seeing what you want to see and coming to a misguided opinion.
Lets be honest here, if Evans had been marking Ulloa and Ulloa scored we would be blaming Evans for not winning the header, not stopping the cross, not being strong enough, being out of position, not taking control of the box or any other reason that comes to the top of our heads, while the other three defenders and midfielders who didn’t track back off scot free.