Porto striker Jackson Martinez has yet to decide where he will play next season with Arsenal, Tottenham Hotspur and Chelsea all keen.The London clubs are all looking to boost their attacks with Arsenal over reliant on Olivier Giroud, Spurs needing more support for Emmanuel Adebayor and Chelsea looking to address their lack of goals scored by forwards.Martinez was reported to have already put pen-to-paper with Napoli but those reports appear to be wide of the mark.The Colombian has been in superb form this season scoring 27 goals in 46 games with interest in the striker well documented with Manchester City and Manchester United having also expressed an interest earlier in the season.Martinez has a release clause of 33m, which the player’s agent recently hinted has still not yet been met, though he claims there have been offers.Some clubs are interested in knowing the details about his situation and opening negotiations, Luis Henrique Pompey was quoted as saying by Portuguese daily A Bola.If it is good for all parties, I view it as normal that it will end in a sale.