Totchtawan Sripan urged his Bangkok United side to keep fighting after the Angels dropped crucial points in a 2-2 draw with Lamphun Warriors in a Thai League 1 game on Thursday night.
Anan Yodsangwal's 62nd-minute equaliser secured a point for Lamphun as the Angels twice threw away their lead in the match at Thammasat Stadium.
Second-placed Bangkok United have 50 points from 24 games, three behind leaders Buriram United. There are only six games left in the season.
Everton Goncalves put the Angels ahead in the 12th minute before Akarapong Pumwisat equalised for Lamphun 10 minutes later. Rungrath Poomchanthuek fired Bangkok ahead again on 36 minutes before Anan's second-half leveller.
"We will try to do our best in the remaining six games of the season," said Angels coach Totchtawan. "The players seemed to lack motivation in this game and we have to rediscover that winning mentality again."
Thai League 1 action resumes this weekend after a 10-day break for the Songkran festival.
The Thunder Castle could open up a six-point gap with a victory at Ratchaburi's Dragon Solar Park Stadium today. Bangkok United will visit Nakhon Pathom tomorrow.
Supachai Chaided, Naruebodin Weerawatnodom and Guilherme Bissoli are all ready to start the match for the Thunder Castle, who will be favourites to take three points against sixth-placed Ratchaburi.
Also today, fourth-placed BG Stadium United welcome struggling Chonburi FC.
Meanwhile Thai football chief Nualphan Lamsam has been named as Chief Executive Officer (CEO) of the Thai League Co, Ltd, after the board committee meeting on Friday.