The tweet came after Kelly scored the Reds' second goal in their 2-0 win over Chelsea at Stamford Bridge in the League Cup quarter-final on Tuesday evening.
The 21-year-old tweeted: “Written in the stars, I appologise to jay speo as he owes me money from a bet we had for first senior goal.”
Kenny Dalglish’s men snatched their second victory over Chelsea in under a fortnight after their 2-1 Premier League victory.
Craig Bellamy, who was absent from Liverpool’s draw in the Premier League with Manchester City on Sunday, made an emotional return to the starting line-up, following the death of friend Gary Speed.
But the Welshman was in fantastic form, terrorising the Blues defence and setting up both goals.
First, Bellamy squared for Maxi Rodriguez to tap into an empty net, while the second was a beautifully flighted free-kick which Kelly rose to head past Ross Turnbull in the home side’s goal.
Kelly has been kept out of the starting line-up by an in-form Glen Johnson for much of this campaign, but will be hoping his assured performance against Chelsea will remind Kenny Dalglish that he is still fighting for a spot in the first XI.