Left-back Grounds, 24, and forward Franks, 21, will remain at Huish Park on one-month deals, with the view to extending their stays until the end of the season, and Glovers boss Gary Johnson is delighted to strengthen his squad with the Boro duo's signatures.
Commenting on Grounds, Johnson told the club's official website: "I knew about Jonathan's quality when he was at Chesterfield last season alongside Lee (Johnson's son).
"With Kelly Youga out at the moment, he gives me a club in the bag that I don't really have at the moment; that's a defender who can play at left-back or as a left-sided centre-back. He's played at a high level, has good experience and is a good lad."
Asked about Franks' qualities, Johnson replied: "He is very quick, very strong and can play either up front or out wide. He's played at all the England levels from Under-16 to Under-19 and we're lucky to be able to entice players of this quality down here.
"Jonathan has been brought in because we need the reinforcements to the squad ahead of a busy March where we play eight games and we dont wan't to be caught short."
