The France international came off the bench on 66 minutes and helped turn the contest on its head with a clinical brace – his ninth and 10th Premier League goals of the season – to secure three points.
Having grabbed his first goal since New Year's Day in the win over Fiorentina in midweek, Mateta was in confident mood – winning a free-kick within minutes of entering the pitch which led to Jefferson Lerma thumping a header off the crossbar.
But Mateta and Palace were not to be denied, and the forward was in the right place at the right time after 80 minutes to round off a fine team move, heading home a clever pull-back from Tyrick Mitchell.