Southampton and Swansea's bosses have hit out at their wantaway stars short-changing supporters by missing Saturday's Premier League season opener at St Mary's.Saints wasted a hatful of chances in labouring to a goalless draw with Swansea on the south coast, where Virgil Van Dijk and Gylfi Sigurdsson were conspicuous by their absence.Southampton boss Mauricio Pellegrino and Swansea manager Paul Clement both admitted their clubs and supporters are missing out while their top stars remain out of action.Saints defender Van Dijk officially sat out with a virus but continues to agitate for a transfer, while Swansea have opted not to select Sigurdsson as he edges ever closer to a big-money move to Everton.Asked if everyone loses out when transfer sagas keep the best talent off the pitch, Swansea boss Clement replied: "Fans, team-mates, coaches, the viewers all around the world; absolutely."What would be a better situation would be if the transfer window closed before the start of the season."I don't really understand why it goes to the end of August."I know there's talks about that changing in future. And that's my opinion that it should do."Dutch centre back Van Dijk could well end up at Liverpool by the end of this transfer window.If Philippe Coutinho forces through his move to Barcelona from Liverpool, then the Reds are likely to raise their bid for Van Dijk and prise the ex-Celtic man away from Southampton.New Saints boss Pellegrino has inherited the club's latest transfer tug-of-war, and conceded that such scenarios are no good for the game."I can't manage all the situations like some players being outside the team; it's not my responsibility," said Pellegrino."But it's a pity because the people deserve to see the best players in the pitch. It happens and we have to keep going."Southampton dragged their St Mary's goal drought to 545 minutes in a frustrating stalemate against a dogged but limited Swansea, the visitors clearly struggling without Sigurdsson and the injured Fernando Llorente.Swansea boss Clement admitted his side were fortunate to sneak a point, then admitted he hopes for a quick resolution over Sigurdsson.When quizzed on links to Stoke's Joe Allen, Clement replied: "I'm not going to speak about incoming players."The only situation that's important at the moment is the Gylfi Sigurdsson transfer situation."If that does go through then we can start acting on potential targets. I want to do that kind of stuff in private until there's something certain."There's a situation where both clubs have not agreed, there's a difference of opinion on the valuation of the player. But I don't think it's far away now."Southampton boss Pellegrino remains far more upbeat about his unsettled star's potential future at the club however, continuing to insist there is a way for Van Dijk to reintegrate into Saints' side."When you are outside the team you have to be behind them, supporting them," said Pellegrino."Hopefully he can change his point of view to be with us in the next few weeks."I've talked with him (Van Dijk) twice, and the club was clear with him."I think all of us at the club, the technical director, me as a manager, we know that Virgil is an important part of the club."But we need him in another way, not like the way he is right now."