The Young Lions beat USA 2-0 to complete a clean sweep in the Four Nations Tournament, having already won against Germany and the Netherlands.
At Rochdale's Spotland stadium on Monday, Roberts started to win his second international cap while Armstrong came on in the 63rd minute as late goals from Ovie Ejaria and Dominic Solanke gave England victory.
Meanwhile at senior level, Matz Sels was on the bench for the duration of Belgium's 6-0 win against Gibraltar.
Siem de Jong - who is on loan with PSV Eindhoven - was an unused substitute as Netherlands lost 1-0 to France in a World Cup qualifier.