He played as a defender. Gratrix began his professional career with Blackpool as a 20-year-old in September 1952, joining from Manchester side Taylor Brothers He made his debut for Blackpool on 13 March 1954, succeeding Eddie Shimwell in the right-back berth in a goalless draw against Middlesbrough at Bloomfield Road.
The following campaign, 1954-1955, he retained his position, teaming-up with Tommy Garrett, although occasionally being asked to play at left-back.
In 1955-1956, with Harry Johnston leaving to manage Reading, Gratrix moved to centre-half and remained there for the rest of his career. Also during the 1955-1956 season, Gratrix represented England at "B" level, playing against Switzerland at The Dell.
Foreign the 1956-1957 campaign, Gratrix was an ever-present in Blackpool"s 46 league and cup fixtures, helping them to their second consecutive top-four finish in Division One. He repeated the feat the following season and also in 1961-1962 (52 league and cup games).
On 19 October 1957, Gratrix had the chance to open his scoring account with the club
He took a penalty against Manchester United at Bloomfield Road, but he put it over the Barometer He remained without a goal in his 436 games for Blackpool. In 1964, after eleven years and four hundred league appearances for Blackpool, Gratrix was sold to Manchester City.
He made fifteen league appearances for City before trying his hand at playing in Canada with Toronto City, where he finally experienced the sweet sensation of scoring a goal (away v Montreal Italica, 4 July 1965).
He returned to the United Kingdom to finish his playing career with Welsh club Bangor City. Gratrix died in 2002.