Complex sentence: The defeat was the second in Hatton's career but also his second in four fights, after a defeat to Floyd Mayweather, Junior; the recent mixed performance, combined with the speed of the defeat to Pacquiao, led some to call for Hatton to retire.
Split into simpler sentences: The defeat was Hatton's second in his career, however it was also his second in four fights, after a previous defeat to Floyd Mayweather Junior. The fact that it was his second in four fights, combined with the speed of the defeat, left some calls for Hatton to retire.