Fognini was down 1-4 -- having had his serve broken twice -- in the first set before coming back for a 7-5, 3-6, 6-0 win over Martin Klizan.
Klizan had a pair of breaks in each the first two sets but wasn't able to hold onto the early lead. Fognini took over in the third set, winning two-thirds of the points to close out the win.
Roberto Bautista Agut claimed a 3-6, 7-6 (7-5), 6-3 decision over eighth-seeded Kevin Anderson. Bautista Agut had his serve broken once, which lost him the first set, but saved all six of the break points he faced in the second and third sets.
Anderson didn't see a break point in the first two sets but Bautista Agut went 2-for-4 in third-set break opportunities.