The referee, Anthony Taylor, deemed it a penalty, and a red card
“LIVERPOOL, England — Romelu Lukaku’s second half was not an especially glamorous one. There was a lot of running, darting into the slivers of space on either side of Liverpool’s central defenders, hoping for a ball that rarely came. There was a substantial amount of tussling and wrestling with Joel Matip, in particular, the two scrabbling for every inch of ground. There were not, conversely, many touches: only 20 in all after halftime, not quite one every two minutes. …”
NY Times
Guardian: Chelsea show resilience to survive Anfield’s medieval battle scenes