Didier Drogba kept Chelsea's faint title hopes alive with a late winner against Portsmouth at a rain-soaked Fratton Park. The Ivory Coast international pounced to convert a low cross from Jose Bosingwa to hand the interim coach Guus Hiddink his fourth straight win as Chelsea boss. It leaves them four points behind the leaders Manchester United who still have two games in hand on the Blues. But Chelsea were made to battle all the way by Pompey who remain just two points off the relegation places at the foot of the Barclays Premier League. The home side had Chelsea rocking from the off when a free-kick from Glen Johnson provided Hermann Hreidarsson with a clear chance but his effort from eight yards was deflected wide. The game was being played in atrocious conditions with rain sweeping down onto the Fratton Park playing surface. The pitch was extremely slippery and made ball control difficult for both sets of players. In the 16th minute, Chelsea should have taken the lead but Drogba was inches away from putting the finishing touches to a drilled cross from Ashley Cole. The Ivorian flung himself at the ball but missed it by inches at the far post. Moments later a clever ball by Frank Lampard put Drogba through but the Chelsea striker's shot was charged down by the onrushing David James. Chelsea continued to have the better of the exchanges and in the 21st minute Florent Malouda flashed an angled 20-yard drive beyond the far upright. Seconds later Chelsea were unable to take advantage of an error by James. The Pompey goalkeeper allowed a cross from Malouda to slip out of his grasp in the wet conditions but Sean Davis cleared for a corner. The Blues had goalkeeper Petr Cech to thank for keeping the score line level in the 28th minute when he dived to his right to keep out a powerful low drive from Davis. A foul by John Terry on Peter Crouch on the edge of the penalty area brought Pompey a free-kick but Johnson smashed his effort straight into Chelsea's defensive wall. James failed to hold Lampard's 20-yard drive in the 34th minute but again Chelsea were unable to make the most of it as the ball bounced out of his hands. Chelsea were now beginning to assert some consistent pressure for the first time in the game but the conditions were preventing them from playing the neat passing game they rely on. Long passes through the middle for Drogba to chase also had little effect with the ball skidding off the surface and out of play on numerous occasions. Three minutes before the break a goalmouth scramble from a Pompey corner ended in relief for the visitors when Cech pounced to grab the ball inside the six-yard box. Chelsea almost broke the deadlock in injury time but Michael Ballack's header was just over the bar. In the 59th minute Chelsea had Cech to thank again as a header from Crouch put David Nugent clear but the striker's shot was pushed away by the Czech Republic keeper. Chelsea made two quick changes with Ricardo Quaresma replacing Salomon Kalou and John Obi Mikel making way for Juliano Belletti. Both sides had increased the tempo but had little luck in the worsening conditions. A shot from Belletti was well held by James as it skidded across the turf. The Blues remained in overall control though and in the 66th minute a cross from Quaresma was headed just over by Drogba who managed to get ahead of Sol Campbell. Quaresma was providing an excellent service from the right flank and another cross had to be cut-out by Campbell as Drogba lurked inside the six-yard box. Portsmouth had become penned in their own half and Davis presented the Blues with a free-kick opportunity in the 68th minute when he brought down Lampard. Lampard, normally deadly from 20 yards, sent the free-kick into the ball and Campbell's clearance sent Crouch racing clear into the Chelsea half. The England striker crossed for Niko Kranjcar but the Pompey midfielder sent his effort just wide. But Ivorian Drogba settled the contest when he drilled home a cross from Bosingwa with 11 minutes remaining. *PA Sport