Chris Dagnall scored the only goal of the game as Crewe saw off 10-man Port Vale 1-0 in a feisty encounter at Vale Park.The striker's first-half effort extended the Alex's unbeaten start to the season to four league games and secured them bragging rights over nearby Vale.Vale, who had veteran midfielder Michael Tonge sent off after a reckless challenge 11 minutes before half time, have now lost their last three league games.Crewe took the lead after 30 minutes when Dagnall beat the offside trap to nod in George Cooper's ball from the left.Just four minutes later Vale were a man light when Tonge saw red for a high tackle on Cooper.The home side almost restored parity after 52 minutes when Tom Pope's back-post header hit the crossbar and bounced on the goal-line, before Marcus Harness' follow-up was cleared off the line.Vale continued to press for an equaliser, but their search ended in vain as Rekeil Pyke hooked Pope's header wide of the upright.