Liverpool are the reigning champions of the EFL Cup, having defeated Chelsea in extra time at Wembley last season, with Virgil van Dijk scoring the decisive goal. The competition sees all 72 football league clubs entering from the first round, while Premier League teams join in the second or third round if they are involved in European competitions. Middlesbrough was the most successful team from outside the top flight last year, reaching the semi-finals. Millwall's head coach Neil Harris has handed Daniel Kelly, an 18-year-old midfielder, his debut in their second-round tie against Leyton Orient, making eight changes from the team that drew with Hull City, including starts for Femi Azeez and Macaulay Langstaff.