Porto are prepared to double the salary of Colombian striker Jackson Martinez in an attempt to ward off reported interest from elsewhere.
The 27-year-old has been in prolific form since arriving at the Estadio do Dragao from Mexican side Chiapas in 2012, netting 33 goals in 37 appearances since the start of last season.
Napoli were believed to be closing in on his signature during the summer transfer window, while Arsenal were also said to be interested.
However, the Daily Mail reports that Porto are about to offer him a 100% pay increase to £45,000 per year, which would also involve renegotiating his release fee from £31m to £45m.
The two-year extension would see him contracted to Porto until 2018.