They say it is the biggest humiliation a footballer can experience: being a substitute that, after getting on the pitch, is then subbed off. So why did Hansi Flick bring on Marcus Rashford for 30 minutes on his Barcelona debut - and then take him off again?

Rashford, 27, appeared for the first since completing his season-long loan move from Manchester United in midweek, ending his exile at Old Trafford. The forward's transfer - which includes a £26million option to buy - was finalised in time for him to fly to Japan with the rest of Barca's squad, as they embark on a pre-season tour of Asia. First up was a clash with Japanese side Vissel Kobe in a friendly match which was initially suspended before organisers scrambled to make it happen.

Rashford was named on the bench by Flick before the German changed his entire line-up at half-time. The United loanee showed promise during his 30-minute cameo, notably playing a crucial role when fellow new signing Roony Bardghji got on the scoresheet in Barcelona's 3-1 win.

After defender Jofre Torrents won back possession on the left, Rashford collected the ball and played a perfectly-weighted pass through to Robert Lewandowski. Barca's No.9 then picked out Bardghji on the right, as the former Copenhagen hotshot produced an impressive first-time finish.

Seconds later, Rashford was brought off. The England international and Torrents were replaced by Gerard Martin and Pedro Fernandez, scorer of Barcelona's third goal, in the 77th minute.

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Post-match, Flick was asked about his decision to haul both Rashford and Torrents off after half an hour each.

"Rashford hasn't played that much, and we also wanted to give Gerard Martin 15 minutes because he was playing after his injury," the Barcelona manager explained. Which, obviously, makes perfect sense for a player who, just seven days ago, was a member of Manchester United's 'bomb squad' training alone and made to use the club's Carrington training ground when the first-team squad had gone home.

For Flick, these early days are about getting Rashford up to speed, slowly but surely, helping him adjust to what he wants. Do it correctly, and it's another match winner among Barca's collection of stars. Subbing him on and then off in a pre-season friendly? Not a problem for the manager nor his new player.

Will Marcus Rashford be a success at Barcelona? Give us your prediction in the comments section.

Flick was a 'key' reason why Rashford joined the La Liga champions, having led Barcelona to three trophies in his first season. "He was another key factor for me to join Barca," the 27-year-old revealed during his unveiling.

"The conversations I had with him were very positive. He has proven to be one of the top coaches... He led a young team to such a successful season and has returned to the preseason wanting more."

Rashford's team-mates are already looking forward to playing alongside him. "Rashford is a very talented player," Lewandowski told reporters in Japan.

"We played Manchester United two years ago and he was in great form. He can help us and is able to play in different positions."

Next up for Barca is a friendly against Seoul in the South Korean capital on Thursday. Rashford will have a reunion with ex-United team-mate Jesse Lingard, who captains the K-League giants.

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