Albion are level at the break after taking the lead against West Ham through Glenn Murray after just 10 minutes.
Albion had other chances, most notably through Anthony Knockaert, to increase their lead.
However, just after the half hour Javier Hernandez waltzed through the Seagulls defence to equalise for the visitors.
Leo Ulloa got a rousing reception from Seagulls fans when he warmed up along the touchline.
The Albion might need the man from Argentina in the second half.