By 1976 he was a first-choice midfielder who was a prolific goalscorer for someone in his position; his first goal for the club came in the 68th minute of the 3–2 league win over Tottenham Hotspur at Anfield on 23 August 1975.

Bob Paisley thought it was time for Jimmy to move on, especially because whenever Case attended a local event, he ended up with dozens of pints on his table, bought by appreciative fans.

Case joined Brighton in August 1981 as a £450,000 makeweight when Mark Lawrenson went the other way and he played a large part in the success achieved at the Goldstone Ground in the early 1980s.

The game ended 2–2 with Brighton passing up a great opportunity to win the cup when Gordon Smith hit a shot directly at United keeper Gary Bailey, who pulled off a spectacular save.

In spite of this setback, Case remained at the Goldstone Ground for nearly two years after the Seagulls were relegated, including a further FA Cup victory over Liverpool in January 1984.

In March 1985, Case moved to Southampton for a nominal fee of £30,000 as Lawrie McMenemy's last signing for The Saints, to replace Steve Williams, who had been transferred to Arsenal in December 1984.

Over his six years at The Dell, Case lost none of his bite in the tackle and he made up for any loss of pace by a broadening vision and excellent passing skills.

Case played in midfield alongside Glenn Cockerill and Barry Horne and helped to bring on the careers of exciting young players such as Le Tissier, Alan Shearer, Rod Wallace and Jason Dodd.

He played there for 6 months, before moving on to Wrexham, where he helped them gain promotion from Division Three at the end of the 1992–93 season, while Halifax fell into the GM Vauxhall Conference.