NBC was in full control of Tuesday’s primetime ratings race in young adults, winning each hour among the major networks behind “Food Fighters,” which spiked in its second week, and the steady “America’s Got Talent,” which again was the night’s top program.

According to preliminary “live plus same-day” Nielsen estimates, “Food Fighters” averaged a 1.3 rating/5 share in adults 18-49 and 4.8 million viewers overall in the 8 o’clock hour — up 30% (0.3) from its premiere of last week for the largest regularly scheduled week-one to week-two gain in adult 18-49 rating point for any new Big Four series in at least two years.

The 1.3 for “Food Fighters” (pictured) beat the 1.2 of the second episode of ABC’s “Rising Star” for the top week-two result among the five new reality shows to bow on the Big Four this summer.

It was followed by “America’s Got Talent” (2.4/8 in 18-49, 10.5 million viewers overall), which matched last week’s demo score while rising a bit in total viewers.

At ABC, “Extreme Weight Loss” (1.1/4 in 18-49, 3.7 million viewers overall) was up a tenth to match its highest 18-49 rating in eight weeks, and the season finale of “Celebrity Wife Swap” (1.0/3 in 18-49, 2.8 million viewers overall) was also up a tick.

CBS aired repeats of crime dramas “NCIS” (1.0/4 in 18-49, 8.3 million viewers overall), “NCIS: Los Angeles” (1.0/3 in 18-49, 6.4 million viewers overall) and “Person of Interest” (0.7/2 in 18-49, 4.5 million viewers overall). And Fox went with encores of comedies “Family Guy” (0.7/3 in 18-49, 1.8 million viewers overall), “Brooklyn Nine-Nine” (0.5/2 in 18-49, 1.1 million viewers overall), “New Girl” (0.5/2 in 18-49, 1.0 million viewers overall) and “The Mindy Project” (0.5/1 in 18-49, 1.1 million viewers overall).

Univision ranked second on the night in 18-49, led by 9 p.m. telenovela “Lo Que la Vida Me Robo” (1.5/5 in 18-49, 3.7 million viewers overall).

Preliminary 18-49 averages for the night: NBC, 2.0/7; Univision, 1.4/5; ABC, 1.0/3; CBS, 0.9/3; Fox and Telemundo, 0.6/2; CW, 0.3/1.

In total viewers: NBC, 8.6 million; CBS, 6.4 million; ABC, 3.4 million; Univision, 3.3 million; Telemundo, 1.5 million; Fox, 1.3 million; CW, 0.8 million.