Sol Campbell watched nine-man Southend lose 7-1 just hours after being appointed as their new manager.
The former England centre-back, who left his role as Macclesfield boss in the summer, has signed a deal until the end of the 2021/22 season at Roots Hall.
Campbell takes over a team second from bottom of League One with just one win from 15 games after being hammered 7-1 at home to Doncaster on Tuesday night.
Campbell kept Macclesfield in League Two against the odds in his first managerial role, having taken over last November with the side seven points from safety, but he faces arguably an even tougher task at the Shrimpers.
Southend are already eight points from safety, with only crisis-club Bolton keeping them off the foot of the table, and have taken just one point from their last five games.
His first match in charge will be at home to leaders Ipswich on Saturday.
The 45-year-old will be assisted by Hermann Hreidarsson, while former Manchester United striker Andy Cole has been named as his forward and attack coach.
Hreidarsson and Cole, both former team-mates of Campbell at Portsmouth, also worked under him at Macclesfield, who survived on the final day of last season.
His new club said in a statement that Campbell was "determined to push on and make his mark at Southend United with the help of his backroom staff".
Southend have turned to Campbell after scrapping plans to appoint former Celtic and Sweden striker Henrik Larsson.
The club have been searching for a new permanent manager since the resignation of Kevin Bond in early September.
Before his appointment at Macclesfield, Campbell had spoken out repeatedly about the barriers for aspiring Black, Asian and Minority Ethnic (BAME) coaches.
