London - Shane Warne is keeping cricket fans in both England and Australia guessing on whether he is ready to make a stunning comeback to Test cricket during the ongoing Ashes series.England's crushing innings and 71 run win in the second Test at Adelaide this week, which put the Ashes holders 1-0 up with three to play, has left Australia facing the prospect of losing a series to their oldest rivals on home soil for the first time since the 1986/87 season.Such has been the Australian attack's lack of penetration that in England's last two Test innings they've taken a mere six wickets for a huge collective total of 1 137 runs.That has intensified the clamour amongst fans and some sections of the home media for Australia leg-spin great Warne to return to national service even though it is nearly four years since the 41-year-old, who has 708 Test wickets to his credit, retired from the five-day format following the 5-0 Ashes whitewash of England in 2007.Warne flew in to London on Wednesday for a promotional visit and then told social networking site Twitter: "Just landed in London, it's freezing and was welcomed by press and photographers asking am I making a comeback?"What have I missed???"The Victorian has not exactly encouraged such calls but, ever the showman, he hasn't exactly discouraged them either.Earlier, in his column for London's Daily Telegraph newspaper, Warne, also a television cricket pundit and chat show host, wrote: "There has been a bit written in Australia and people have been asking me about making a comeback."All I can say is that it is very flattering to hear those words."Prior to Australia's 2009 Ashes series loss, Warne - as he has yet to do this time around - said he would answer an emergency call from Australia captain Ricky Ponting."If there were no other spinners around and Ricky came out and said 'Mate, can you please help us out for this one-off tour, we need you' that is something I would weigh up," Warne said at the time.Australia decided they could do without him then and, even if Warne makes himself available, would they pick him now?Andrew Hilditch, Australia's chairman of selectors, is under intense scrutiny.As a Test batsman Hilditch was ridiculed for the way he repeatedly fell into a hooking trap during England's 1985 Ashes series win, but if he recalled Warne only for the move to be unsuccessful, the fall-out would be something else.Warne is still playing for Rajasthan Royals in the Twenty20 Indian Premier League (IPL) but the Victorian's last competitive game in what is professional cricket's shortest format was in April.And ex-England off-spinner Shaun Udal said he found it hard to believe Warne, his captain when they played for English county side Hampshire, would return to Test duty during the Ashes."He's not played four-day or five-day cricket for the last three or four years," Udal told Sky Sports. "He's only played Twenty20 cricket."To be out of the international, particularly the Test match arena for such a long period of time and then to walk straight back in would be a tough ask, even for a great such as Shane."But former England captain Andrew Flintoff, the standout performer alongside Warne during England's 2005 Ashes series win, said he would be genuinely delighted to see the spin star back playing Test cricket."I'd love to see Warnie play again, it would be unbelievable," Flintoff told the Melbourne Herald-Sun."Warne's aura would bring something to the side, he'd make a difference in the dressing room," the now retired all-rounder added."They're missing that bloke to give the rest confidence - for 15 years, the guy who did that was Shane Warne."