A few people have mentioned it. Someone also suggested ESPN+ while using a VPN (US) - I couldn't get either to work my end so I didn't take any chances as I couldn't get to the first leg tie annoyingly.
Instead I purchased a monthly subscription on NowTV for about £26. I watched the Bolton - Barnsley game last night, the first leg and will be watching tonight. For one game it's £14.99 which is quite excessive, however for a month £26 isn't terrible as a one-off.