Former Liverpool defender Mark Lawrenson has warned Harry Maguire that his place in the Manchester United starting XI may not be secure, despite remaining club captain.The 29-year-old made his first appearance under new boss Erik ten Hag during the Red Devils' 4-1 win over Melbourne Victory in a pre-season friendly on July 15. Maguire was present on the pitch when the A-League outfit scored within the first five minutes.Footymemes.21@footymemes21Harry Maguire starts for Man United and they conceded in 5 mins against Melbourne Victory1714184Harry Maguire starts for Man United and they conceded in 5 mins against Melbourne Victory😭 https://t.co/lhbuazmnu5Maguire endured a miserable campaign last term which was riddled with sloppy mistakes and poor performances. With the impending arrival of Ajax defender Lisandro Martinez, Lawrenson has warned the England centre-back that his place in the Manchester United team could be in doubt.Liverpool legend Lawernson told Paddy Power, as per The Mirror:"Club captain used to mean that you were captain of the club, not necessarily team captain. Harry Maguire is a good player, but like a lot of them last year, he had a really poor season."His problem is that he’s a good footballer, but he is just a bit slow - you can't really make yourself any faster, unfortunately! I don't know whether it'll be him leading the team every week. In all honesty, I would watch this space."Fabrizio Romano@FabrizioRomanoLisandro Martínez, on the verge of signing with Manchester United as deal is almost agreed with Ajax since yesterday - just some final details to be discussed between the clubs on Friday… then, here we go. #MUFCMatter of time, deal in place between all parties.638136491Lisandro Martínez, on the verge of signing with Manchester United as deal is almost agreed with Ajax since yesterday - just some final details to be discussed between the clubs on Friday… then, here we go. ⏳🔴 #MUFCMatter of time, deal in place between all parties. https://t.co/Jm4NFv40shErik ten Hag concerned by Manchester United's defending during pre-season friendly in MelbourneManchester United made it two wins from two under their new manager in their ongoing pre-season. Yet, after the encounter at the Melbourne Cricket Ground, Ten Hag was more focused on what could be improved.The Dutch boss made a real point of showing how disappointed he was in his team's defending for the goal, as he said (quoted by The Mail):"I don't want to talk about the individual because I think it was from the start high up the pitch: the wrong choices and then it ends up like a pack of cards. It's not one individual, it is more the team who made mistakes."But we turned the game around, that was the really good thing. We don't come down, we react, and we deal with the setback."The 52-year-old will be desperate to tighten up a defense that conceded 57 Premier League goals last season - more than what relegated Burnley conceded. Ten Hag has, so far, started his reign in pre-season playing four at the back, but he has experimented in the past with a five-man defense.Vida Abena@UtdKwamzBailly should bench Harry Maguire34044Bailly should bench Harry Maguire https://t.co/MxRP0cuGy4.