Bauerfeind's brother Reiner, who stepped up from the Rovers club's division one team as a starter for the first time this season in the 18th-round encounter, took on the role as target striker. Fellow striker and club stalwart Andy Pickering hadn't been able to train for two months because of a back injury.
In his final outing before returning to the US to resume commitments with the West Virginia University Mountaineers, regular striker Andy Bevin was forced into a midfield role as he didn't have the energy to play up front after a bout of food poisoning last week.
The Rovers' woes continued when the versatile David Gearey was forced off with a calf strain in the 15th minute. Gearey, regular midfielder and captain for the day in Robertson's absence Cole Peverley, and regular wide player Josh Stevenson all had to play in relatively unfamiliar roles as defenders.
This trio, along with regular wide right player Harley Rodeka - who was playing right fullback - were still coming to grips with their roles when Wairarapa United scored in the first minute. Another who had his first outing for the side this season was Rhys Brew, who took the field in the 15th minute as a midfielder after playing 90 minutes for the club's reserve grade side the previous day.
"It was pretty obvious we were three or four class players short and considering the list everyone battled well," Hastings said.
He singled out Rodeka, midfielder Scott Henderson and Morgan for their high work rates. Another example of the lack of depth in the side which travelled south is the fact teenage striker Harry Fauntley is still two years away from being up to the standard required at this level, according to Hastings.
Wairarapa led 4-0 after 30 minutes and this was the score at the halftime whistle. Strikers Seule Soromon and Brian Kalteck were able to get the ball behind the Rovers defence regularly with ease.
Hastings pointed out the welcome from Wairarapa United fans wasn't as hostile as he had expected in the wake of last month's Chatham Cup controversy. It was the Rovers club which initiated the protest that saw Wairarapa United disqualified from the Cup after a third-round 2-1 win in Napier for using an ineligible player.
"One wag in the crowd on the other side from us kept yelling out to check that player's eligibility but apart from that there was nothing else," Hastings said.
The loss is a severe blow in the side's quest to reach the top four. Rovers host Upper Hutt City at Park Island on Saturday in the first of four remaining games in the league.