Guardiola has previously worked with Messi at Barcelona, where they won the Champions League on two occasions.
Yamal has been hailed as one of the best players to emerge from Barcelona's youth academy, La Masia, since Messi's departure.
When asked about the comparisons between Yamal and Messi, Guardiola said that it's unfair to make such comparisons and that Yamal should be allowed to continue his career without the pressure of being compared to someone else.
Guardiola used an analogy to explain his point, saying that comparing Yamal to Messi is like comparing a painter to Vincent van Gogh, and saying that they're not as good, which isn't a fair assessment.