"I think about missing out on winning the title all the time. I know I've got plenty of years left in me at Liverpool, but even when you're at your peak, you start thinking about the time it may start going the other way," said the vice-captain.
"When I get to the end of this contract, if we still haven't won the title, it's natural I'll be starting to worry about how many chances I'll have left.
"I'm desperate to realise that ambition of winning a Premiership medal during the course of this contract.
"Football time flies so quickly. It doesn't seem that long ago people were talking about Stevie and myself as the youngsters who could be part of a successful Liverpool team for a long time.
"Even the three years Rafa has been here have flown. In another three years I'll be 32 and a few in the Kemlyn Road will be saying I'm finished!"