London: Chelsea have stumbled on the path to next month's Champions League final. They were held to a 0-0 draw by Liverpool in an uncompromising first leg of their semi-final at Stamford Bridge yesterday. The English champions-elect could find no way through a superbly-marshalled Liverpool defence in the first all-English semi-final in the competition's history. Liverpool, who drew 0-0 at Juventus in the quarter-finals to reach the last four 2-1 on aggregate, employed the same defensive approach with a stifling five-man midfield. Jose Mourinho's jaded-looking team failed to beat Liverpool for the first time in four meetings this season.