FA Cup progression is the aim for Sunderland this weekend - but they will face a stern test against a Walsall side eyeing revenge.
The Saddlers will be something of a familiar test for Jack Ross' side given the pair met as recently as last weekend but, given the Black Cats' late heroics that day, Walsall will no doubt be keen to right the wrongs.
So what should Ross and Sunderland expect this weekend?
Here's an in-depth look at the Saddlers
What system will Walsall play?
Walsall tend to operate in a traditional 4-4-2 formation, although they have been known to switch things up to combat the opposition.
Two lively and attack-minded wide players provide the ammunition for a talented front two, who have looked lively throughout the season.
The front line is very much based on youth, with a clutch of promising youngsters starting to flourish.
Further back, however, the Saddlers benefit from some real experience with the solid bank of four at the back proving difficult to penetrate.
Who are Walsall’s key players?
A blend of youth and experience provides the key for Walsall, with their promising youngsters having hit the headlines this season.
And they will prove key as the Saddlers look to avenge the Black Cats' late leveller last weekend.
Perhaps the most recognisable name in the Walsall side is that of Russell Martin - the former Norwich and Rangers centre back who joined the club in the summer.
Further up the field, the lively Zeli Ismail has caught the eye with his performances - the former Wolves wideman impressing on the left flank.
In the centre of the park, youngster Liam Kinsella has impressed in recent weeks after injuries presented him with an opportunity.
And up top, former Carlisle and Tranmere striker Andy Cook has hit the goal trail after making the step up from non-league, having netted eight times already this season.
Do Walsall have any injury worries?
Walsall have no fresh injury worries, meaning manager Dean Keates could opt to name an unchanged side from that which lost at Portsmouth in midweek.
Versatile Joe Edwards is nearing a return, but the visit of the Black Cats is expected to come too soon for him.
Who is Walsall’s manager and what can we expect from them?
Dean Keates is the man in charge at Walsall after impressing in his first managerial job at Wrexham.
A former midfielder, Keates playing career saw him represent the likes of Peterborough, Wycombe and Walsall - with the 40-year-old returning to his former club as manager in 2018.
He enjoyed great success at Wrexham with an attack-minded style, so expect similar from the Saddlers this weekend.
What form have Walsall been in?
Walsall don’t enter the FA Cup in the best run of form, having won just one of their last eight League One outings.
Following their 2-2 draw with Sunderland last week, the Saddlers fell victim to a 2-0 defeat at league leaders Portsmouth.
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