Bayern Munich raid, £21m signing, four exits - Man United's dream defence after seven transfers

The plane carrying Manchester United's squad to the United States for their pre-season tour touched down in Los Angeles on Wednesday without a senior left-back on board.

United have left Tyrell Malacia at home to continue working on his recovery from a long-term knee injury and Luke Shaw is away after representing England at the European Championship.

As a result, the only recognised left-backs that have gone to the US are youngsters Harry Amass and Sam Murray. They trained with the first-team squad at times last season and have both featured in each of United's opening two friendlies this summer.

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As highly as United rate the two academy prospects, there are concerns about the state of the left-back department. Malacia has not kicked a ball since appearing for the Netherlands on June 14 last year and Shaw played just 16 times in all competitions last term.

With that in mind, it is clear United would be wise to strengthen at left-back before the end of this summer's transfer window with the addition of another senior figure. As reported by the Manchester Evening News on Wednesday, Feyenoord's David Hancko, who is reportedly valued at between £21million-£42m, and Marcos Alonso are being considered.

When he is fit and available, Shaw is a guaranteed starter for United. He was outstanding in Erik ten Hag's first season at Old Trafford and the Dutchman rates him highly, so much so he described him as the 'best left-back in the world' in May.

However, it is impossible to avoid his injury record; the highest number of appearances he has managed for United in a single season is 47, achieving that in