His effort was enough to earn Bristol City their second away win of the season, completing the double over Vale and lifting the Robins off the foot of the League One table.
Vale's injury ravaged line up included 36-year-old youth team coach Andy Porter who last started a game at Vale Park back in May 1998.
With three team starlets on the bench Vale were down to bare bones, yet they had a great chance to go ahead as early as the second minute when Birchall fired over.
That was the queue for the visitors to come out of the starting blocks and Bristol soon had Vale pegged back in their own half.
Vale's injury problems increased when former City favourite Mickey Bell limped off after 20 minutes. Michael Husbands came off the bench and Vale reshuffled.
Dave Cotterill went close when he curled an angled shot wide of the target with Mark Goodlad beaten, and then Louis Carey went even closer.
His eight- yard effort in the 37th minute left Goodlad flat-footed but the ever reliable Porter was on hand to clear off the line.
Brooker hit a brace for the Robins when the two sides met at Ashton Gate back in August and on the stroke of half time he hit one again.
Allowed to turn just inside the Vale box he fired hard and low to the keeper's right, squeezing the ball inside the far upright to put City in front.
Vale stepped things up after the break and the visitors were forced to defend in numbers for long periods where keeper Basso was rarely tested.
Vale eventually ran out of steam becoming more and more frustrated as the game went on and in the end the visitors were good value for their three points.