Manchester United are placed fourth in the Premier League table, ahead of Arsenal and Chelsea, but it still doesn't take away the fact this has been their joint worst start to a Premier League campaign after collecting only five points from their first four games, before a narrow win in their last match. On paper, it could have been a lot worse even in their opening game of the season against Chelsea when the scoreline ended up being 4-0 in their favour.Losing to Crystal Palace at home in the manner that they did coupled with defensive lapses against Southampton and Wolves exposed the dark cloud of last season. A 1-0 win over Leicester City, courtesy Marcus Rashford's penalty, did little to inspire confidence. Yes, the team created some chances but were not clinical enough. A better defensive performance and David De Gea enabled United to preserve the clean sheet.Without Paul Pogba, United showed that they didn't have another midfield player who could take charge of the game. Nemanja Matic stabilised the ship but his advancing age came into play as he was unable to stay sharp for the full 90 minutes thus substituted. A few adjustments could get United performing better which should be enough to beat some of the teams that cause them problems with each passing week.Marcus Rashford is one designated set-piece taker for the club.#3 Set piecesIn tight games, it is set pieces that can get a team over the line. Manchester United need to find set piece routines and takers that work for them. In a match they could have all of Harry Maguire (6 ft 4), Scott McTominay (6 ft 4), Nemanja Matic (6 ft 4) and Paul Pogba (6 ft 3) as target men in the box.Maguire, in particular, poses an aerial threat and he is sometimes spotted as trying to direct the set-piece taker on where he wants the ball played. This is a testament to the fact that he is a leader and wants the ball. Being more clinical in set pieces including converting penalties can give United more goal options.Harry Maguire is a good target man from set-pieces.