The defender, who is valued at €8m (£6.8m), has represented England 10 times at under-21 level but has made just two Premier League appearances this season.Southampton, who were last removed, have now been warned. Russell Martin’s side are locked in a battle to bounce back at the earliest opportunity. Ipswich Town remain second with three points, but are four points adrift of Leeds. It is believed that they see Johnson as the ideal player to help them in the second half of the season.They are not alone and the search for his signature promises to be interesting. Sheffield United have acknowledged interest by briefly offering Premier League football but are likely to return to the Championship in May. Scottish giants Rangers are also in the hunt – they could offer European football now that they have reached the last 16 in the Europa League, which could please Johnson.Johnson is out of contract at the end of the season and as he is 24, West Ham will not be charged. That means any potential suitors can snap him up for free in the summer, or pay a modest fee now to get ahead of the competition.The Saints have yet to make any major changes in the transfer market this winter, with Joe O’Brien-Whitmarsh arriving from Irish outfit Cork City for a mere fee of an undisclosed fee.Writer’s ViewBen Johnson is becoming hot property. At 23, he is an asset whose value is likely to rise and he can operate on either flank, making him a versatile addition to the squad.He is also available for what many would consider a bargain price. If he waits until the summer, it could mean a bigger payday for him, but if he moves now, it will restart the season.Among those chasing his signature, Southampton and Rangers certainly stand out. The Saints are in prime position to offer Premier League football next season, although that is clearly not set in stone, while Rangers could immediately push him into the European spotlight.He is likely to become a Rangers regular, but by moving to Scotland he would be giving up the big games that English football and possibly the Premier League brings..