Spain's Bautista-Agut began the clay encounter the sharper of the two players and having broken Simon's service early on, he went on to record a 6-3 success in the opening set.
Another break followed in the second set, which saw the world number 52 open up a 4-2 advantage.
However, Simon responded on this occasion to level up the scores at four games apiece. Breaks were then exchanged between the two players, which ended with the set entering a tie-breaker.
Bautista-Agut took control of the breaker immediately and he soon found himself with four match points. Simon saved all of those, but he was eventually defeated 8-6.