TalkSPORT are reporting that the Saints and the Blades have verbally agreed on a loan deal which is believed to include a clause which could see the move made permanent in the summer.
The Chile international had scored six in 14 Premier League games for the Blades in the second half of last campaign. This season however he has struggled to find his feet with zero goals in 13 appearances for the Saints.
He has not started a league match since September and new manager Ivan Juric is said to have no hesitation in loaning him out to title-chasing United who would likely welcome him back with open arms.
Manager Chris Wilder was asked if there was a chance of incomings before Thursday night’s FA Cup tie against Cardiff City.
“Potentially. We’re working overtime. There’s incredible support from the owners and Stephen Bettis, who are also working overtime. They see what everyone else is seeing (about the squad’s strength) and the supporters are seeing it as well.”