Flintoff is the X-factor in series against the Proteas: Vaughan

England cricket skipper Michael Vaughan has described all-rounder Andrew “Freddie” Flintoff as the “X-factor" in the remaining two Tests against the South Africans.

Freddie is set to take on South Africa at Headingley on Friday after proving his injury hell is behind him.

Flintoff has not played a Test for 18 months due to ankle and side problems.

The Sun quoted Vaughan as saying: "I always had it in the back of my mind to get Fred back into the team.

"He just needed another game to prove himself. He''s not a wizard, he''s not going to come and sprinkle dust, he''s just going to come and perform how he can. But he does have that bit of X-factor about him,” Vaughan added.

"When you give him the ball he can create something and in the past when he''s gone out to bat, he''s made things happen. He can also take wonderful catches,” Vaughan said.

England missed him at Lord''s but he impressed for Lancashire against Hampshire, bagging three wickets and scoring 39 not out in a six-wicket win.

South Africa batting hero Neil McKenzie said: "We will give him the respect he deserves."

Out-of-form Paul Collingwood is most likely to make way. (ANI)