Saido Berahino???s wonderful half-volley after just 72 seconds was enough for a 1-0 victory with Southampton failing to score for the third game running.
Koeman, whose side remain in fifth, had little complaints about the result but was left frustrated with the way Tony Pulis??? side wasted time after scoring the opening goal.
The Southampton manager could be seen at various points of the game speaking to the fourth official about West Brom???s philosophy of slowing the game down meaning his side couldn???t generate any momentum to their game.??
West Brom goalkeeper Ben Foster was booked in the second-half for running down the clock but Koeman thought the referee should have done more. ??
???In my opinion, it was too much,??? said Koeman.??
???It???s not the reason we lost today, but there was only one card throughout the 90 minutes for time-wasting. The referee is there to try to bring that back. We said things to the referee but it wasn???t enough. There was a lot of time-wasting, but, OK, that???s part of football.???
West Brom have improved immensely since Pulis took over and they are now eight points clear from the relegation places while Southampton have suffered a blip in form but still are only two points off Arsenal in fourth place.
Koeman still thinks his side are in a good position but admits confidence is low within the camp, especially with his attacking players. ??
???We knew it would be a difficult game, they have been doing well in the last few weeks, keeping clean sheets and winning points,??? he said.??
???We start the game and after one minute you are one-nil down. That makes it more difficult as they dropped very back in the defence and had a very good organisation. For us it was too difficult to break it open. We had one or two chances in the game but the goal in the first minute was enough for them and to defend the result.
???The team performance in the last few weeks is a little bit more down ??? apart from 45 minutes against Liverpool. We???ve lost confidence in creating chances and scoring goals.??
???We didn???t have a lot today but in one or two of them we had to score. But we have to keep going. We are in a good position in the table but next Tuesday against Crystal Palace we have to win because we need those points.?????