 Complete the following phrase:  Jimmy McStay, who made over 400 appearances for Celtic as a player and captained the side, was appointed manager in 1940. However, his tenure would be during the war years, a period when Scottish football suffered huge disruption. He also had to contend with increased boardroom interference, which he never managed to quell. The result was stagnation with little tangible success. In the summer of 1945, McStay reluctantly resigned at the behest of the board and was succeeded by another celebrated former player, Jimmy McGrory. The early years of his reign were very poor, and in 1948 the club only narrowly avoided relegation. Matters improved in the early 1950s with the 