LONDON, Jan 29 (Reuters) - Liverpool's "soft" young players must work harder or they risk ending up playing in the same league as Oldham Athletic, who knocked them out of the FA Cup, manager Brendan Rodgers has warned. The seven-times cup winners were roughed up by the third- tier side in a 3-2 defeat on Sunday that prompted the Liverpool manager to question whether some of his young charges had the desire to succeed at the top.