Kat, played by Jessie Wallace, arrives back in Albert Square on Thursday, June 7.
Viewers will see Roxy (Rita Simons) admit her crush and tell Kat how Alfie (Shane Richie) rejected her, the Daily Star Sunday reports.
Kat will make it clear to Roxy that she is no longer welcome to live or work at The Queen Vic.
"Everyone has been eagerly awaiting Kat's return to Albert Square and it doesn't disappoint," a source told the paper.
"Roxy confesses all in a bid to stay on friendly terms with Kat and Alfie. He then decides the best distraction would be to set up a football team."
Scott Maslen (Jack Branning), John Partridge (Christian Clarke) and Tameka Empson (Kim Fox) were spotted filming the special football scenes on location yesterday. Get the Inside Soap magazine on your iPhone or iPad