LONDON — Xabi Alonso is set to be named Chelsea coach after reaching an agreement with the Premier League club, a person with knowledge of the situation told the Associated Press on Saturday. The person spoke on condition of anonymity because the appointment has not been publicly announced. Alonso talked with Chelsea in the past week and is expected to sign a four-year contract. It would be the Spaniard’s first job since lasting less than eight months at Real Madrid. Alonso left Madrid by