Birmingham have agreed a £6m deal to sign Jota from Brentford.
The Spaniard is on his way to the Blues for a medical.
Sky Sports have reported that a £6m fee has been agreed and Redknapp told talkSPORT this morning: “We are very, very pleased to have got that one done”.
Boro saw an offer in the region of £4.5m rejected last week and reports on Wednesday had suggested Jota was keen to stay in the capital.
It is thought Boro were determined not to be drawn into a bidding war for a player who was due to enter the final year of his contract at Griffin Park.