NEWCASTLE United are hoping to conclude a swift deal for Dutch-based duo Douglas and Erik Pieters when the transfer window reopens this summer.
However, the Magpies are set to face stiff competition from both Arsenal and Tottenham if they step up their interest in a third target currently playing in Holland, highly-rated Ajax centre-half Jan Vertonghen.
Having stolen a march on their rivals to land Yohan Cabaye in the early months of last summer, Newcastle officials are hoping to make early inroads for the second close season in succession.
Alan Pardew is desperate to improve his side's defensive options, and in conjunction with chief scout Graham Carr, the Magpies manager has identified Douglas, a centre-half at FC Twente, and Pieters, a full-back at PSV Eindhoven who is also capable of playing in central defence, as his preferred options.
Preliminary discussions are understood to have taken place with FC Twente, and while Steve McClaren would like to keep Douglas for one more campaign, his Dutch employers are ready to cash in on the £5m-rated Brazilian.
Newcastle have received similarly positive noises about Pieters, a player who has been attracting their attention for the best part of 18 months.
The Holland international has expressed a desire to leave the Eredivisie at the end of the current campaign, and Newcastle are confident the promise of European football will help lure him to Tyneside.
Last month, St James' Park sources hinted that the capture of two experienced defenders would account for the bulk of the Magpies' summer spending, but the situation is now in a state of flux as the club waits to learn which European competition it will be playing in next season.
Qualification for the group stages of the Champions League, which would be reliant on the negotiation of a qualifying-round tie if Newcastle were to finish in fourth position, would result in a guaranteed windfall of around £20m.
A chunk of that money would be made available to Pardew for squad strengthening, and to that end, the Magpies manager was in Holland at the weekend to watch Ajax at first hand.
Belgium international Vertonghen is believed to have been his primary focus, but Newcastle face a heated battle if they are to step up their long-standing interest in a defender rated at the £10m mark.
Both Arsenal and Tottenham have sent scouts to watch the 24-year-old in recent weeks, and sources in London claim the latter are particularly keen to secure his services given their lack of options at centre-half.
Spurs' summer transfer plans will be influenced by what happens to Harry Redknapp in relation to the England manager's job, but the club's interest in Vertonghen is already at an advanced stage and it is expected that chairman Daniel Levy will pursue it no matter who is in charge at White Hart Lane come the start of next season.
Arsenal scouts have been similarly impressed with Vertonghen's recent displays, and provided the Gunners secure Champions League football, the presence of his fellow Belgian, Thomas Vermaelen, at the Emirates Stadium could prove significant.