Park Ji-sung is adamant Manchester United's players must take collective responsibility for replacing Paul Scholes.[LNB] Sir Alex Ferguson has already spoken of the difficulties involved with trying to cover Scholes' retirement.[LNB]The United boss believes trying to find a like-for-like alternative to one of the finest players of his generation is virtually impossible.[LNB]Arsenal's Samir Nasri looked like a useful replacement but Ferguson has long since concluded the France international will be heading for Manchester City if he leaves the Emirates Stadium.[LNB]Wesley Sneijder is clearly a player of immense talent but huge difficulties remain in trying to get the Dutch star to Old Trafford from Inter Milan.[LNB]Ferguson continues to scour the planet for players of potential.[LNB]However, there is a possibility United will head into the new campaign with the players they already have.[LNB]And if that is the case, Park uses the exit of Cristiano Ronaldo two years ago as proof of how Scholes' loss should be overcome.[LNB]"We have to do it together," he said.[LNB]"When Ronaldo left the club everyone said it was bad for the team but we still managed to perform and win trophies.[LNB]"It was just one player. We had to make up for that together. It is the same with Paul Scholes."[LNB]Clearly, it is not just in talent that Scholes will be missed.[LNB]The former England star's vast experience is lost to the dressing room too, especially in the wake of Edwin van der Sar's retirement, which followed so quickly after that of Gary Neville.[LNB]Wes Brown and John O'Shea had also been at Old Trafford for over a decade before leaving for Sunderland, although again, Park believes there are alternatives.[LNB]"We still have a lot of experienced players; Rio Ferdinand, Ryan Giggs, Nemanja Vidic, Patrice Evra," he said.[LNB]"They have all been at Manchester United for more than five or six years and all have great experience.[LNB]"They can replace the likes of Paul and Edwin van der Sar."[LNB]Park might have added his own name to the list.[LNB]After all, he is about to start his seventh season as a United player.[LNB]And with Ferguson revealing the South Korean has been offered a two-year contract extension, Park obviously has a pivotal role to play in the seasons that lie ahead.[LNB]To that end, he is bound to be helped by quitting the international scene, for even he acknowledges there was a price to be paid for all those frequent trips back to Asia.[LNB]"The fitness levels do get affected when you travel so much and play extra games," he said.[LNB]"I hope to get more rest, not suffer any injuries and enjoy the season."[LNB]A goalscorer in both United matches on their pre-season tour of the United States so far, Park has started in impressive form, which he hopes to maintain.[LNB]He acknowledges the Champions League defeat to Barcelona in May hit his team-mates hard, although with a 19th Premier League title collected as well, reaching definitive conclusions has been tricky.[LNB]"The Barcelona game was very disappointing," he said.[LNB]"Every player had the same feeling and it left us with mixed thoughts because we also won the title, which allowed us to make history.[LNB]"However, we have to do better because what happened against Barcelona hit us hard. It was such a disappointing defeat.[LNB]"We have to think of the future. We have to be better and must work hard to try and ensure that doesn't happen again."