The 31-year-old centre-back has moved to Wearside from Stoke City, signing an 18-month contract at the Stadium of Light.
To find out more we caught up with Stoke reporter Peter Smith to get the inside track:
Why has Batth been allowed to leave Stoke?
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PS: “Probably three reasons.
“Firstly, he perhaps wasn't the best fit for the style Michael O'Neill wants to play. Stoke built the team around Harry Souttar building out from the back and Batth isn't a natural like-for-like replacement as Souttar's out for the season. Souttar likes to start moves, Batth is first and foremost a stopper.
“Secondly, two defenders came in so it makes sense for one to leave, especially to balance the wage budget.
“And thirdly, all the players who signed deals before the pandemic are out of kilter with the post-pandemic budget, especially because that also coincides with Stoke losing parachute payments. Batth was a senior player so it would make sense for him to be at the higher end. O'Neill must believe he can better use that money in other areas.”
What are his strengths and qualities?
PS: “He loves defending. If anything moves, he'll kick it or head it. He's brave and he's a leader, a natural old-fashioned captain. He's a decent threat at set pieces too and has a knack for chipping in with important goals.”
What is he like on the ball?
PS: “He's not Franz Beckenbauer but he knows his own strengths. He'll not want to take risks but he won't want to just whack it clear.
“O'Neill said recently: ‘Danny knows his options, he knows what his passing range is and knows the passes he plays well.
‘It’s about giving him clarity but that’s not just down to Danny, it’s down to the structure of the team in front of him and the options he has to play with.
‘Danny has been working hard on this since pre-season. We’ve played consistently with a back three and everything we do in training is with a back three so he’s well versed in training about doing the same things that Harry (Souttar) has been doing.’
How will he be remembered at Stoke?
PS: “A whole-hearted no-nonsense centre-half who always played with pride for the badge. That's not been a given over the last few years and it's very much appreciated. He'll get a warm reception if he ever comes back as an opponent.”
Do you think he could still play in the Championship?
PS: “He's a proven Championship defender. Let's not kid ourselves, a lot of the Championship isn't sexy, it's about defending set pieces or balls launched into the box and winning battles in three-game weeks. He was Stoke's player of the month for doing all that in November.
“But no one should be surprised that he hasn't turned his nose up at League One.
“He doesn't want to just kick about as a fringe player or be happy at some mid-table club. He wants to be at a big club and win promotion. Stoke fans will be wishing him well.”