A.T. Robertson Commentary Mark 11:20

"And as they passed by in the morning, they saw the fig tree withered away from the roots." — Mark 11:20 (ASV)

As they passed by in the morning (παραπορευομενο πρω). Literally, passing by in the morning. The next morning. They went back by the lower road up the Mount of Olives and came down each morning by the steep and more direct way. Hence they saw it. Matthew 21:20 does not separate the two mornings as Mark does.

From the roots (εκ ριζων). Mark alone gives this detail with εξηραμμενην perfect passive predicate participle from ξηραινω.