Former Chelsea defender Tal Ben Haim's own goal helped Andre Villas-Boas' Blues edge a 1-0 victory over Portsmouth at Fratton Park.[LNB] Having played their 3-0 midweek victory over Wycombe behind closed doors, the Blues fielded completely different line-ups in each half as the recently-appointed Portuguese boss gave all his players a chance to gain pre-season fitness at Fratton Park.[LNB]Villas-Boas' side failed to get out of second gear in the first period but took the lead in the seventh minute when Ben Haim calamitously headed into his own net.[LNB]Substitute goalkeeper Hilario produced a superb save to stop Luke Varney's penalty after the break to help Chelsea eke out victory on the south coast.[LNB]Villas-Boas chose to start the match with a blend of youth and experience, with the likes of Fernando Torres, Ashley Cole and Florent Malouda lining up alongside youngsters Billy Clifford and Tomas Kalas.[LNB]Portsmouth, meanwhile, made three changes to the side that beat Havant & Waterlooville on Monday as Herman Hreidarsson, Ben Haim and Stephen Henderson came in for Jason Pearce, Lewis Stockford and Jamie Ashdown.[LNB]Portsmouth came close to breaking the deadlock within the opening three minutes when David Norris burst down the left flank and only a smart block from Ashley Cole prevented the incoming Dave Kitson flicking home at the near post.[LNB]But despite the flash of attacking intent, it was the visitors that began the brightest and were given a lead through a bizarre own goal from Ben Haim.[LNB]Torres' cross from the right was mis-hit by Greg Halford as he attempted to clear, resulting in the former Chelsea defender heading into his own net.[LNB]Villas-Boas' troops continued to press after taking the lead, with Torres somehow heading a gilt-edged chance wide before John Obi Mikel fizzed a free-kick straight at goalkeeper Henderson.[LNB]Despite Chelsea's dominance, Portsmouth did muster a few chances of their own and tested Ross Turnbull on several occasions.[LNB]The former Middlesbrough keeper was first forced to stop Norris' bundled header sneaking home, before palming wide Luke Varney's thumping drive as half-time approached.[LNB]Chelsea started the second period with an entirely new XI, while Portsmouth - who could only name five substitutes - brought on Ashdown and Pearce.[LNB]The half began at a lackadaisical pace and the only moment of note was 30-yard free-kick from Hreidarsson.[LNB]However, the game soon livened up when substitute Hilario was adjudged to have brought down Luke Varney and referee Keith Stroud pointed to the spot.[LNB]The former Blackpool striker stepped up confidently but was thwarted by the Portuguese goalkeeper's outstretched hand down low to his left.[LNB]Dave Kitson flashed a shot wide as he looked to atone for Varney's miss, before Didier Drogba and Yossi Benayoun had efforts at the other end.[LNB]Hilario's good work twice almost came undone after defensive miscommunication saw Varney hare into the box to try and score, but Nathan Chalobah and Jose Bosingwa's blushes were spared by last-ditch defending on both occasions.