Having sluggishly won his opening two matches, the Swiss won his third-round encounter much more convincingly.
But will he struggle again against a much better player in David Goffin?
Last year the 20-time Grand Slam champion disappointed and bowed out at the fourth-round stage to Australian John Millman, inciting the intense heat as a factor in his defeat.
However, Roger Federer has looked below par again in New York. He surprisingly dropped the opening set to Indian qualifier and world number 190 Sumit Nagal before powering through 4-6, 6-1, 6-2, 6-4.
A namesake not to be confused with Spanish 18-time Grand Slam champion Rafael Nadal.
In the following round, Bosnia's Damir Džumhur won the first set before Federer eventually prevailed 3-6, 6-2, 6-3, 6-4.
A routine 6-2, 6-2, 6-1 win over Britain's Dan Evans will do little to convince the critics considering the scheduling controversy that irked the Swiss after the match.
Where journalists implied that stature alone forced the organisers' hands unto scheduling the third-round encounter into an early lunch-time slot.
Following Thursday's rain delayed finish for Evans in his win over France's Lucas Pouille, this left the Brit sapped of energy after a less than 24 hours turnaround to take to the court.
While a later night match would have been much more in Evans' favour and given him adequate time to recover and play the Swiss.
A cheesed off Federer told journalists, his preference was the lunch time slot for US Open organisers, but that the TV stations were the ultimate decision makers.
A resurgent Belgian now awaits the Swiss in round four.
Goffin enjoyed a memorable 2017 as he catapulted himself into the world's top 10 which included a fine win over Federer at the end of year Tour Finals in London before losing in the final to Bulgaria's Grigor Dimitrov.
Both Goffin and Dimitrov have been in somewhat decline for the past season and a half as the Belgian slipped outside the world's top 20. As for Dimitrov, he slipped alarmingly outside the world's top 50.
The difference for Goffin is that he has steadily improved this year in 2019. A strong grass-court season laid the foundations for the former world number 7's return to form.
The Belgian made the final of Halle in Germany before ultimately losing in straight sets to Federer coincidentally. This was backed up with an impressive run to the quarter-finals of Wimbledon for the first time.
Then came the American hard-court summer where Goffin sneaked under the radar to make his first Masters 1000 final in Cincinnati before eventually losing to Daniil Medvedev.
Add to the mix the French Open prior to Wimbledon back in May. Goffin was the only player to take a set off Nadal as the Spaniard stormed to an unprecedented 12th French Open title.
Goffin will be a huge step up for Federer make no mistake. The Belgian is a tricky opponent, who hustles for every point. Not dissimilar to Spain's newly retried hero David Ferrer.
Goffin has a good forehand and boundless endurance. Whatever frame of mind Federer is in following the scheduling debacle, he must be solely focused on winning.
He will need a fast start and fans of the Swiss will be praying it is a much easier ride than two of his previous three matches. But knowing Goffin's fighting qualities, Sunday's clash won't be easy.