LONDON (AFP) Pakistan captain Shahid Afridi has challenged his side to build on last weeks Twenty20 wins over Australia in the two-Test series between the countries that starts at Lords here on Tuesday. Pakistan failed to win a single international match on a tour of Australia concluded this year, sparking a series of bans and fines imposed on several players by the Pakistan Cricket Board (PCB). The fall-out meant a youthful squad arrived in England without its two leading Test batsmen in former captains Mohammad Yousuf and Younus Khan, who both had disciplinary action taken against them by the PCB. But the way Pakistan beat Australia in back-to-back Twenty20s at Edgbaston, suggests a bowling attack featuring Umar Gul and teenage left-arm quick Mohammad Aamer, and set to be bolstered by leg-spinner Danish Kaneria and paceman Mohammad Asif, will pose problems. However, the key factor in determining the outcome of the series is whether Pakistans batsmen can score enough runs. If they can, they could yet triumph in a series being played in England after top-class international cricket in Pakistan was suspended following last years armed attack on Sri Lankas team bus in Lahore. Leg-spinning all-rounder Afridi, who hasnt played Test cricket since 2006 in order to concentrate on one-day formats, became captain despite being penalised himself for biting the ball in Australia. Nevertheless, it appears his side are rallying behind him and Afridi said: I think now we have regained our winning habit, we must work harder to maintain it. But he admitted Yousuf and Younus had left a large hole in Pakistans top-order. Obviously we will miss their experience, Afridi said. But right now I am focusing completely on the team I have. They are the ones who will fight for Pakistan in the Test matches and I retain confidence they can do this. In the absence of Yousuf and Younus, who both average over 50 in Tests, the only member of the Pakistan top six who averages more than 40 is the gifted Umar Akmal and he has played just six Tests. I think their depth is going to be tested, Australias Michael Hussey said. You take Younus Khan and Mohammad Yousuf out of that team and youre losing two outstanding, classy players. Thats going to be a big loss, particularly in the Test match arena, the left-handed middle-order batsman added. Its going to be very hard to find those runs that those guys consistently score in Test match cricket. But their bowling attack looks outstanding. Theyre very well balanced and they cover all bases very well. Pakistan who, if the Twenty20s are any guide, can be assured of vocal backing from British-based supporters, are embarking upon a run of six Tests in seven weeks, with four matches in England against their hosts after the Australia series It is a very hectic schedule, said Pakistan coach Waqar Younis. It is a tough tour for the youngsters, but also a learning tour for them. In many ways, it is like a restart for Pakistan, Waqar, one of the outstanding fast bowlers of the 1990s, added. It is also a landmark series as it will be the first time Tests in England have not featured England since the 1912 triangular tournament, where Australia and South Africa made up the three competing teams. Meanwhile, both Australia wicketkeeper Tim Paine, deputising for the injured Brad Haddin and leg-spinner Steven Smith are likely to make their Test debuts at Lords. And with Paine and swing bowler Ben Hilfenhaus set to join captain and star batsman Ricky Ponting in the XI, Tasmania - a state with just two-and-a-half percent of Australias population - could have three players in the Test side for the first time.