The 31-year-old defender was Boro's first summer signing when he arrived from Bolton last July, but five days after completing the deal he was injured 20 minutes into the opening warm-up game with York City at Bootham Crescent.
Although he is yet to play senior football for Boro, Baptiste recently returned to action with Paul Jenkins' U-21 side and played two games in central defence. He is equally comfortable in both full-back positons, and the move to Sheffield United, which includes a recall clause after the first 28 days, is seen as an opportunity for him to return to action at a senior level.
After starting his career at Mansfield, he enjoyed some of the best moments in his career helping Blackpool win promotion to the Premier League in 2009-10. Prior to joining Boro, he spent a season on loan to Blackburn from Bolton.
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