UPDATED: The viewing levels were way down Friday, suggesting it could be a long, hard summer for the broadcast networks.

But ABC could still celebrate winning the night with two hours of "Shark Tank" and an edition of "20/20." The Disney-owned network had both the most viewers and the most young adults.

"Shark Tank," which has become a viewer favorite for ABC, ended the season with back-to-back episodes. The first drew 5.1 million, and the second brought in 6.7 million, according to updated ratings. The second was the night's top program with the 18-to-49 age group so important to advertisers.

At 10, ABC had more good news with "20/20" drawing 5.5 million and outperforming two other news magazines. "Rock Center With Brian Williams," which NBC has canceled, drew 5 million. CBS' "48 Hours" had 4.3 million fans.

The bright spot of CBS' night was the season finale of "Undercover Boss" at 8 p.m. with 5.6 million viewers. An "Undercover Boss" rerun at 9 had 5.1 million fans.

NBC opened the night with a two-hour "Dateline" drawing 5.3 million.

The prime-time averages: ABC with 5.8 million, NBC with 5.2 million, CBS with 5 million, Fox with 2.2 million for reruns and The CW with 920,000. On The CW, "Nikita" ended its season with 1 million fans. The CW announced Thursday that the thriller will get a six-episode farewell next season.

In Orlando, "20/20" was tops with 104,500 viewers. The 9 p.m. "Shark Tank" was second with 98,400. Rounding out the top five were "Undercover Boss" with 94,900, "Dateline" with 86,700 and the 8 p.m. "Shark Tank" with 73,500.