Once again proving itself to be the hottest tandem in late night, the combination of Jimmy Fallon and Justin Timberlake drove NBC’s “The Tonight Show” to its best ratings since Monday’s premiere.

Friday’s episode of “The Tonight Show Starring Jimmy Fallon,” which featured frequent collaborator Timberlake as a guest, scored a 6.1 overnight metered market rating. Up from Thursday’s 5.3, it was second only to Monday’s 7.1 during this strong “Tonight” premiere week.

Overnight household ratings for the first five “Tonight” episodes were as follows: 7.1, 5.3, 5.2, 5.3, 6.1.

Friday’s “Fallon” scored a 3.0 adults 18-49 rating in the Top 25 markets with Local People Meters. For the week, the preliminary adults 18-49 numbers were as follows: 3.4, 2.3, 2.2, 2.4, 3.0