Jimmy may have had the biggest night but it was still Jay that had the biggest week in latenight.

Nielsen numbers released Thursday showed that NBC’s “Tonight Show with Jay Leno” narrowly prevailed last week in the key adults 18-49 demo over ABC’s “Jimmy Kimmel Live” (999,000 vs. 956,000), with both shows rounding to a 0.8 rating. In total viewers, Leno averaged 3.53 million to 2.86 million for Kimmel.

CBS’ “Late Show with David Letterman,” in repeats, was third in both 18-49 (762,000) and total viewers (2.56 million).

It’s been a competitive 18-49 race thus far between Kimmel and Leno, with the former winning their first head-to-head encounter and Leno now prevailing by smallish margins the last two weeks.

“JKL” had its strongest nightly showing since switching to 11:35 p.m. last Thursday (1.30 million adults 18-49, 3.64 million viewers overall) with an hour that featured Matt Damon taking over the show; it was higher-rated than any night of “Tonight” for the week.

And in total viewers, this was Kimmel’s largest audience ever for a regular episode.

Kimmel was also the youngest-skewing of the three 11:35 p.m. broadcast talkshows, with a median age of 54 vs. nearly 57 for both Leno and Letterman. “JKL” topped “Tonight” in adults 18-34 for a third straight week (330,000 to 314,000). ABC’s “Nightline” also drew its best 12:35 a.m. numbers last Thursday (761,000 adults 18-49, 2.15 million viewers overall), though the show remains well behind its 11:35 p.m. levels of last year as expected.

Also in latenight for NBC, last week’s “Saturday Night Live” hosted by “The Voice” judge Adam Levine set a season high in adults 18-49 (2.7 rating/10 share or 3.44 million viewers in the demo) and the best score for the show since May 12 of last year (hosted by Will Ferrell). And in total viewers, last week’s 7.27 million is the largest “SNL” audience since an episode last March hosted by Lindsay Lohan.