Manchester United manager Erik ten Hag during the Pre-Season Friendly football match between Manchester United and Rayo Vallecano on July 31, 2022 at Old Trafford in Manchester, England – Photo Alan Martin / Colorsport / DPPI (Photo by Alan Martin / Colorsport / DPPI via AFP)Erik ten Hag’s first competitive game as manager on Sunday should herald a fresh start for Manchester United, but familiar failings behind the scenes have made the Dutchman’s difficult job an almost impossible one.Ten Hag’s predecessor Ralf Rangnick signed off from his miserable caretaker spell last season by stating the United squad needed “open heart surgery” and up to 10 new players after labouring to a sixth-placed finish in the Premier League.So far, only three new faces have arrived at Old Trafford — Lisandro Martinez, Tyrell Malacia and Christian Eriksen.The United squad is arguably weaker than last season with Paul Pogba, Edinson Cavani, Jesse Lingard, Nemanja Matic and Juan Mata having left for free, while goalkeeper Dean Henderson has joined Nottingham Forest on loan.The prospect of a much more significant departure is set to hang over the first few weeks of the season with Cristiano Ronaldo trying to force his way out to play Champions League football this season.Ronaldo made his first appearance of pre-season on Sunday, playing in the first half of a 1-1 draw against Rayo Vallecano.But his decision to then leave the stadium before full-time was branded “unacceptable” by Ten Hag.The former Ajax boss has shown a disciplinarian streak during his early weeks in charge, reportedly reintroducing fines for bad time-keeping and banning the players from having their own personal chefs.Ten Hag has shown no signs of appeasing Ronaldo’s ego, ordering