The first encounter between West Brom and Wolves in the Premier League was overshadowed by trouble which started when a smoke bomb was thrown from the visiting fans' section into the home crowd at The Hawthorns.
The home supporters responded by hurling objects back at the Wolves fans, one of whom was pictured with blood streaming down his head.
The FA's crowd control officer at the game will report back on what he saw.
Meanwhile at Millwall on Saturday referee Chris Sarginson had to stop the game on two occasions and even considered calling the match off after Middlesbrough keeper Jason Steele and the assistant referee were the target of bottles and other objects thrown from the crowd.
The trouble began after the assistant allowed a Scott McDonald second-half goal to stand despite the player appearing to be in an offside position.
An FA spokesman said: "We are awaiting the match officials' report and we will be seeking observations from both clubs."
Middlesbrough ended the game 3-2 winners.