This is something we’ve rarely seen in the past couple of years — a No.1 Thursday finish for NBC. The network tied CBS and Fox for the top spot among adults 18-49 on the night where it had struggled mightily this past season. Burn-off comedy series Undateable showed spunk, premiering with a 1.3 in 18-49 at 9 PM. It built onto its lead-in, Hollywood Game Night (1.2, up 9% from last week) to post NBC’s highest rating with regular programming in the 9-9:30 PM slot since November 7. Undateable almost doubled the debut of another midseason-turned-summer comedy on NBC last year, Save Me (0.7 on 5/23/13) to post the highest-rated summer comedy premiere on the Big 4 networks in five years (since ABC’s toon The Goode Family on 5/27/2009) and edged one of NBC’s fall Thursday comedy debuts, Welcome To The Family (1.2 on 10/2/13). Undateable also held all of its demo audience for a second episode at 9:30 PM (1.3). Last Comic Standing (1.6) capped the night for NBC with a minimal second-week drop, .1.