Worcestershire are confident going into the first Bears-Pears derby game of the season at Edgbaston, despite the loss of injured all-rounder Gareth Andrew.
Steve Rhodes says his side will be "full of confidence" ahead of the Division One game against Warwickshire.
But the county's director of cricket admits he does not know the extent of Andrew's continuing back problem.
"It's difficult to put a finger on how long. Certainly the next few weeks," Rhodes told BBC Hereford & Worcester.
"He's got to sort out this problem. He'll spend a bit of time on the sidelines. It will be hard for Gareth to get back in until he's done his rehab."
|All-rounder Andrew's ill luck with injury|
|Gareth Andrew made a fine start this season with two half centuries and eight wickets in Worcestershire's first two games, but the fast bowler has suffered a recurrence of the back injury that kept him out for much of 2014.|
|The ex-Somerset man has taken 195 first-class scalps at 32.83. He has also scored 2.413 runs at 23.89 in 75 games since arriving at New Road in 2008 - and has made a name in one-day cricket with his bat.|
On the plus side for Worcestershire, Andrew's absence has again opened the door for fellow fast bowler Charlie Morris, who has followed his 52 wickets in Worcestershire's promotion season in 2014 by so far taking 14 scalps in three games up in the top flight.
"Let's just hope he stays injury free and keeps knocking over top-order batsmen," added Rhodes. "Because, if you can do that, then the world's your oyster."
Morris's career-best match figures of 9-109 in this week's innings victory against Somerset at New Road helped the county to their first top-flight Championship victory since beating Lancashire by 205 runs at Old Trafford in July 2012.
But the last time they came up against Warwickshire in the Championship was two months later, the day they were relegated - and also the day the Bears won the title - at New Road.
And Rhodes is quick to remind his team that they will be coming up against a very experienced Warwickshire side.
|Morris revs up against the major batsmen|
|Seven of Charlie Morris's 14 Championship scalps this season have been openers - more than any other bowler at the other 18 first-class counties|
"Warwickshire are another of those teams quite battle hardened in Division One," he added. "We'll go there obviously full of confidence after beating Somerset, but we expect a very tough encounter.
"We must respect them because you don't become a battle-hardened side without those qualities that get you of jail when you're struggling."
The visitors will be significantly boosted by the inclusion of England all-rounder Moeen Ali, who has been released to play by the England and Wales Cricket Board.
But, while Ian Bell will not has been made available to play for Warwickshire, the Bears are yet to make a decision on Jonathan Trott following his decision to retire from international cricket.
Ball-by-ball coverage of the game on BBC Hereford and Worcester, on 738am, online and on the BBC sport app.