By Wayne Veysey
Arsenal have tabled an improved £21.3 million bid for Sporting midfielder William Carvalho, Goal can reveal.
The Gunners have made a second offer for the midfield anchorman as they try to push through a deal in the final days of the transfer window.
Arsenal are waiting on a response from Sporting Lisbon, who have indicated in discussions that they are prepared to reduce their initial £28m valuation.
The London club have been working on signing Carvalho for many weeks and are now in the final stages of ironing out the complications of his third-party ownership.
As revealed by Goal, Arsenal have already had a £20m bid rejected for the Portugal international. They have returned with an improved offer after securing a place in the Champions League group stages on Wednesday night.
The complex nature of the negotiations mean they are likely to go down to the wire but Arsenal are increasingly hopeful of capturing the 22-year-old before Monday night's transfer deadline.
Sporting are ready to cash in on Carvalho although, according to reports in Portugal, 40 per cent of his rights are owned by investment firm Banco Espirito Santo. The player is also represented by super agent Jorge Mendes, which has added a layer of difficulty to discussions taking place between the parties.
Arsene Wenger has sanctioned a formal move for Carvalho as he seeks to further strengthen his squad in the midfield anchorman and centre-back positions.
The Portugal international started his career in central defence although he is now used more regularly in midfield.
Arsenal are also in the market for an established defender to replace Thomas Vermaelen and provide cover for regular pair Per Mertesacker and Laurent Koscielny.
Goal understands their top targets are West Ham's Winston Reid and Atletico Madrid's Toby Alderweireld.