Saints have completed a deal to sign Spanish midfielder Oriol Romelu.

The 23-year-old Spaniard has agreed a three-year deal at St Mary’s for an undisclosed fee, rumoured to be around £4m.

Romeu adds another defensive midfield option to Ronald Koeman’s squad.

Saints have been actively searching for a player in that role to complement the existing options of Victor Wanyama and Jordy Clasie.

Executive Director of Football Les Reed commented: “We are extremely happy to be able to bring Oriol to the club on a permanent basis.

“Once again, we are demonstrating our commitment to compete seriously on all fronts this season by continuing to build a squad with depth and quality.

“Oriol is a player we have had on the radar for some time – he was a prominent figure in the Chelsea team of 2011/12, when he made 24 appearances as a 20 year-old.

“Like Ryan Bertrand, we believe we have recruited another Chelsea player with an excellent pedigree but also with lots of potential to develop.

“He is another player who matches the Southampton profile – he is young and hungry, has been developed at a top academy and has already played at the highest level with plenty more to come.

“He will complement the qualities we already have among our squad and provide another level of competition for selection.”

Romeu added: “It’s very good to be a part of this club.

“I was looking for a good club and for something new in my career.

“After spending two years on loan, I needed something permanent and a club with a future – and I think I chose the right one.

“Southampton are doing the right things in the last few years and, once they came to me and asked me to come here, from the first day I was hoping to come.

“Now I just want to keep going and to keep developing as a player, and I’m looking forward to start playing as soon as possible.”

Romeu came through the ranks at Barcelona after joining them from Espanyol.

He made two first team appearances for Barcelona before Chelsea paid €5m to take him to Stamford Bridge.

Romeu played 33 times for the Blues over two seasons before a serious knee injury in 2012 halted his progress. He then had season long loan spells at Valencia and Stuttgart.

Romeu has also featured for the Spanish national side at youth level, including at the 2012 Olympics.