The France international was pictured leaving the stadium ahead of Saturday's clash, which finished even after Phil Jagielka's late screamer cancelled out Steven Gerrard's free-kick.
Sakho was left out of the Liverpool squad as Dejan Lovren and Martin Skrtel started in central defence and Kolo Toure was included on the bench.
After the game, Sakho apologised for making a "bad choice".
"I really want to apologise to the club, the supporters and every person who felt offended when I left the stadium this afternoon," he wrote on Twitter.
"I'm aware that it was a bad choice from my part to go isolating to watch the game!"
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