The European champions duly took heed of his warning on Saturday to get their campaign back on track with goals from William Carvalho, Goncalo Guedes, skipper Cristiano Ronaldo and Bernardo Silva helping them to a pulsating 4-2 away victory over Serbia.
The victory lifted Portugal to second place in the group on five points from three games, eight behind runaway leaders Ukraine, who have 13 from five matches after their 3-0 win in Lithuania, and Santos was thrilled with the way his team kept their shape and clicked offensively.
While strikes from forward Aleksandar Mitrovic and defender Nikola Milenkovic ensured that the hosts remained in the game, Portugal was clinical, punishing Marko Dmitrovic’s bungle to nab the opener through Carvalho.
Ronaldo looked subdued in the opening half and was given a hostile reception at Red Star’s Rajko Mitic Stadium, as the Serbian fans jeered him with taunts of “Messi” every time he touched the ball, but he came to life in the second half, netting his 89th international goal.
Santos’ men have a chance to consolidate their position in the group when they head to rock-bottom Lithuania tomorrow, while Serbia travels to Luxembourg, with both sides a point behind Portugal.