Kenny Jackett’s side head to Wetherby Road keen to avoid a giant-killing against their non-league hosts.
The Town currently sit seventh in the National League table – 41 places below the Blues, who reside in 13th position in League One.
And with the game being shown live on BT Sport (7.45pm kick-off), there’ll be many football purists tuning in simply to see a Cup upset.
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Raggett has been privy to such shocks during his career.
Despite being on the wrong end of a third-round 7-0 thumping against Manchester City last season while on loan at Rotherham, he was part of the Lincoln team that got to the quarter-finals of the competition during the 2016-17 season.
Arsenal eventually put pay to the then National League Imps’ heroics by beating them 5-0 at the Emirates Stadium.
But before that, Raggett & Co took the scalps of some notable opposition – including Ipswich and Brighton.
He then scored an 89th-minute winner at Turf Moor to end Premier League Burnley’s hopes of progression in the competition.
The on-loan Norwich central defender, therefore, knows what it takes to spring a surprise and dump an established name out of the Cup.
He’s aware Harrogate will be bidding to do just that against the 2008 winners on their 3G pitch.
But he’s focused on denying tonight’s hosts the chance to add their name to a growing list of giant-killers.
Raggett said: ‘They will be a tough side, I’m telling you.
‘When I was at Lincoln, we beat three Football League sides and then a Premier League side in Burnley.
‘So I am not going to underestimate Harrogate and I know the boys aren't going to underestimate them either.
‘We will go there, be professional and hopefully come away with the win.
‘I played on a couple of 3G pitches back when I was in non-league.
‘It’s a bit different. The ball bounces and rolls a bit different, but we’re not going to use that as any sort of excuse.
‘Hopefully we go there and win the game.’