Boro have just landed Gaizka Mendieta, who is likely to fill the right sided role, but manager Steve McClaren now wants extra midfield options.
Jonathan Greening currently fills the left sided role in Boro's midfield, but McClaren wants to add some competition and has been busy over the last week agreeing deals with Real Madrid and Chelsea for Munitis and Zenden respectively.
Boro agreed terms for 28-year-old Munitis (pictured) earlier this week and they have been discussing terms with the player's representatives.
Racing Santander, where Munitis spent the whole of last season on loan, are the favourites to land his signature but Boro are hoping they can persuade the Spanish international to link-up with his international team-mate Mendieta.
Boro have agreed a one-year loan deal with Madrid for Munitis - something the two clubs are used to doing having done the same thing with Geremi last season and Flavio Conceicao earlier this summer, although he opted to join Borussia Dortmund.
The North East outfit who have suddenly sprung into action on the transfer front have also agreed terms with Chelsea for Dutch star Zenden, but again they are not alone in wanting the Blues winger.
The former Barcelona star has already signalled his intention to leave Stamford Bridge, after the arrival of Damien Duff meant he was unlikely to see much first team action.
Charlton and Dutch outfits Ajax and PSV Eindhoven have already been linked, but Boro have agreed terms - although some sources are indicating that Zenden has already rejected the possibility of moving to Middlesbrough.
The rejection has come in the light of reports that Paris Saint Germain want Zenden to replace Hakan Yakin, whose move from FC Basle fell through last week.
McClaren admitted that Boro want to bring in two more players before next weekend's transfer deadline, one of which is likely to be Danny Mills.
Reports are suggesting that the North Yorkshire-based star has shunned a move to Birmingham City in order to take up a year-long loan at The Riverside.
