England are set to stick as close as they can to a winning formula when they announce their squad for the 3rd Ashes Test.

The enforced absence of the injured Kevin Pietersen leaves England's selectors with a simple equation, retaining the 13 others on Sunday, from an initial 14 chosen last week.

Andrew Flintoff's well-chronicled and ultimately Test career-ending knee problem means England will again have to invest in pace-bowling cover.

That puts Durham pair Graham Onions and Steve Harmison in the frame again, although the former's shoulder injury remains a minor complicating factor.

The only other significant variable might have been the need for an extra batsman, but national selector Geoff Miller has already ruled that out.

Ian Bell was needed as back-up for Pietersen, already known to be struggling badly before Lord's with the Achilles injury which has since required surgery and ruled him out of the rest of the npower series.

But there are no such concerns about any of England's specialist batsmen for Birmingham.

Pitch prediction

Pitch reports from worried groundsman Steve Rouse suggest seam is likely to be favoured over spin after a spell of wet weather in the West Midlands. But in keeping with their preferred continuity policy, England are thought likely to keep Monty Panesar in the squad as a possible second spinner behind Graeme Swann.

Panesar's absence from the Northamptonshire team currently hosting Australia in a three-day tour match supports that theory.

The day-to-day monitoring of Flintoff's knee will be an obvious and constant concern for England this summer, making the contingency of picking an extra seamer a reality in their squad for each of the remaining Tests. Coach Andy Flower spoke plainly about the Flintoff issue after the lynchpin all-rounder's man-of-the-match performance at Lord's had helped England go 1-0 with three to play.

He will have no qualms about having to leave the national hero out, should medical evidence suggest he cannot get through five days.

"I don't think those sort of decisions take an incredible amount of strength," said Flower.

"If guys are fit enough to get through and contribute to winning Test matches then they will be selected. If they're not it's not a tough decision to make - you just don't select him."

Tough question

The Harmison question is perhaps more of a headache.

The Durham fast bowler, who has not featured for Flower's England since Antigua in February, makes a compelling case for a return on the back of 49 first-class wickets for Durham this summer.

Flower confirmed all of the above will be taken into consideration.

"We've got a number of fast bowlers pushing for selection," he notes.

"Harmison and (Ryan) Sidebottom have both done well recently and they're on the fringes pushing hard - which is a great situation to have."

Emotional quotient

It is yet to become clear how reports will be received that Harmison, like his great friend Flintoff, is set to call time on his Test career at the end of the Ashes.

Bell, meanwhile, was being described by Flower as the next batsman in line even before Pietersen was ruled out.

That clearly remains the case for another player who has not featured for his country since February but has notably been retained in recent squads and was pushing hard with runs for his county before two failures in Warwickshire's match at Hampshire.

A policy of banking on Bell with no need for extra cover is, doubtless by design, an expression of confidence in his abilities.

The lack of obvious extra candidates must have played a part too - although Owais Shah is in good heart, Robert Key appears back to form and England Lion Michael Carberry made a double-hundred while Bell was failing twice at the Rose Bowl this week.

Probable Test squad: AJ Strauss (captain), AN Cook, RS Bopara, IR Bell, PD Collingwood, MJ Prior (wkt), A Flintoff, SCJ Broad, GP Swann, JM Anderson, G Onions, SJ Harmison, MS Panesar.