Bath lock Borthwick, due to have been on the bench, misses out for disciplinary reasons.
Borthwick has been cited for alleged foul play during Bath's Premiership defeat against leaders Wasps last Saturday.
He will now face a hearing next Tuesday and, under RBS 6 Nations rules, he cannot play for his country while a disciplinary matter is pending.
Borthwick's place on the bench will be take by Wasps second-row forward Simon Shaw.
