"It's a tough decision for the opposition. They're down 2-1; they think they're in with a chance, of course."
The win gave the Phoenix a four-point lead at the top of the A-League ladder but Merrick said the victory felt hollow.
"We are happy to take three points but our players, we didn't celebrate the win. It's not one of those that you celebrate afterwards."
The Phoenix will turn their attention to hosting Sydney FC at Westpac Stadium on Sunday in a game where they will be light on cattle due to international commitments.
Striker Nathan Burns, one of the form players in the league, will be in Germany with the Socceroos, while a collection of Kiwis have gone to Korea to play for the All Whites.
"I still think we've got a very strong team with good depth," Merrick said. "I feel confident that we can play well against Sydney."
Defender Manny Muscat will return from a shoulder injury this week but Merrick is light on defensive cover given Michael Boxall, Louis Fenton and Tom Doyle will all be in Korea.
Their front three will also need tweaking with Burns and Michael McGlinchey out but that could provide a chance for veteran Joel Griffiths to start, while Merrick will have to assess the rest of his options as the week progresses.
The Phoenix will play four of their final five regular season games at the confines of Westpac Stadium, which bodes well for them to finish near the top of the table going in to the playoffs.
"It's tough climbing the ladder but when you get to the top it's even tougher staying there," Merrick said. "Our challenge will be to stay in the top four."
Wellington are firmly in the race to finish the season with the Premiers Plate and they could book home advantage throughout the finals if they finish the season in first place.
Their run to playoffs is tricky; they finish with matches against Sydney FC (twice), Melbourne Victory, Melbourne City and Central Coast. Only Central Coast are sitting outside the top six.