UPDATE 1-Rugby-Ritchie gets run in new back-row for Scotland v Samoa

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KOBE, Sept 28 (Reuters) - Jamie Ritchie will replace the injured Hamish Watson at flank as one of five changes for Scotland in their must-win Rugby World Cup Pool A clash against Samoa at the Kobe Misaki Stadium on Monday.

Coach Gregor Townsend was desperately disappointed with the showing of his side in their 27-3 opening loss to Ireland and has rung the changes, though Ritchie's inclusion is forced after Watson was ruled out of the rest of the competition.

Magnus Bradbury, who replaced Watson in the squad, also gets a start in the number six jersey, while Blade Thomson takes over at number eight from Ryan Wilson in what is an entirely new back-row in the scrum.

The other two changes are in the backline, where wing Darcy Graham takes over from Tommy Seymour and Chris Harris is at outside centre in the place of Duncan Taylor.

"Samoa are a team capable of scoring points from anywhere on the field. They play an ambitious brand of rugby and their team is full of skillful and powerful players," Townsend said in a statement from Scottish Rugby.

"The reality is we now have to win our next three games to make it out of our pool, so the knockout stages for us begin this Monday night. I firmly believe this group are ready to take on that challenge."

Townsend admitted his bitter disappointment in the way his players had responded against Ireland.

"We had worked hard in our build-up this tournament to deliver our best rugby but we were well below this level in our opening game," he said. "It's been a long week building towards a game where we intend to put a lot of things right."

There will be a personal piece of history to be made for scrum-half Greig Laidlaw, who partners fly-half Finn Russell for the 35th time. That will equal the Scotland record held by Laidlaw's uncle, Roy, and John Rutherford.

Team: 15-Stuart Hogg, 14-Darcy Graham, 13-Chris Harris, 12-Sam Johnson, 11-Sean Maitland, 10-Finn Russell, 9-Greig Laidlaw, 8-Blade Thomson, 7-Jamie Ritchie, 6-Magnus Bradbury, 5-Jonny Gray, 4-Grant Gilchrist, 3-Willem Nel, 2-Stuart McInally (captain), 1-Allan Dell

Replacements: 16-Fraser Brown, 17-Gordon Reid, 18-Zander Fagerson, 19-Scott Cummings, 20-Ryan Wilson, 21-George Horne, 22-Adam Hastings, 23-Duncan Taylor (Reporting By Nick Said; editing by Sudipto Ganguly)