No.16 seed Tommy Robredo stunned world no.1 and four-time former runner-up 7-6 (6), 7-5 in R3 of the Western & Southern Open on Thursday.
The top seed battled past world no.31 Gilles Simon 6-3, 4-6, 6-4 on Tuesday evening in the second round of the Western & Southern Open.
Nole starts his Cincinnati Masters campaign in the second round against world no.31 Gilles Simon.
Frenchman Jo-Wilfried Tsonga ended Novak’s 2014 Rogers Cup campaign with a 6-2, 6-2 win in 63 minutes on Thursday.
Novak battled past Gael Monfils 6-2, 6-7 (4), 7-6 (2) to reach the third round at the Rogers Cup in Toronto on Wednesday.
Novak is a top seed and has a first round BYE. He will open campaign against either Gael Monfils (FRA) or Radek Stepanek (CZE).
Novak won his third Rome Masters crown when he beat Rafael Nadal 4-6, 6-3, 6-3 in the finals on Sunday.
Novak will meet the defending champion and top seed Rafael Nadal for the championship trophy.
Nole beat no.5 seed David Ferrer 7-5, 4-6, 6-3 to advance into the Internazionali BNL d’Italia last four.
Novak came back from a set down to beat Philipp Kohlschreiber 4-6, 6-2, 6-1 and reach his eighth quarter-final in Rome in as many years.