The Reds are due to meet Cadiz on 7 December, before facing Real Betis three days later, with both matches scheduled to be shown live on the United App, ManUtd.com and MUTV*.
However, the boss has stressed he does not want to consider them friendlies, as he wants the Reds at his disposal to show they deserve first-team places when the domestic action resumes before the turn of the year.
"Ah, it's really competitive," said Erik of the two opponents, Cadiz and Real Betis. "It's what I like. I don't like friendlies. You need tough games to be ready for the restart and that is what we are preparing there.