The accolade was awarded for Stevenage's stunning 3-1 win over Newcastle at Broadhall Way in the FA Cup third round clash in January 8 when an own goal from Mike Williamson, a long-range Michael Bostwick effort and an injury-time strike from Peter Winn secured the League Two side a famous victory.
Westley told the club's official website: "There have been some outstanding performances from Football League clubs this season and it's a fantastic achievement to have won this."
He added: "I like to be calm and collected on the sidelines, but when the third goal went in, you can see me with my arms aloft and losing it a bit. That shows how much it meant to everybody."
Source: PA
Source: PA