Tony Mowbray made no excuses after Albion's dismal 3-2 defeat witnessing his defence gift three goals to Newcastle United.
The Baggies were behind after only 73-seconds against the Magpies after Kim Do-Heon failed to intercept in the middle before Leon Barnett slipped over the ball with Damien Duff gladly slotting home through the legs of Scott Carson.
Albion got themselves back into the game only minutes later when Marc-Antonie Fortuné turned Steven Taylor and shot past Steve Harper to even the scores. Peter Lovenkrands made the home side pay with another defensive error as Barnett again failed to clear with Steven Taylor increasing the visitor's advantage from a free header after 41 minutes.
The home side still looked vulnerable at the back after the break but were given a glimmer of hope after Fortuné scored his second of the game following a clever through ball from Filipe Teixeria. Despite pressing in the final 15 minutes Albion couldn't find an equaliser with all talk at the final whistle regarding the Baggies' fragile backline.
"We shot ourselves in the foot today," Mowbray admitted.
"I don't think Newcastle came and did anything special.
"All three goals were gifts for them.
"In the Premier League, you can't defend like that otherwise you're not going to win any football matches.
"Generally, over the last few weeks, we've done okay defensively at home.
"We kept clean-sheets against Middlesbrough and Spurs.
"It doesn't matter who we were playing against today, if you defend like that you can't win games.
"I've got no problems with us going forward and attacking.
"Generally, I think we've sorted out that side of our game with the signings we've made.
"Jay Simpson was a loss today but he and Fortuné have shown the team can score goals with those two in it.
"For 15 games or so, we didn't have them and the goals weren't flowing.
"Unfortunately today, it was at the other end of the pitch where things didn't function for us."
While making no excuses the Albion boss did admit a degree of sympathy towards Leon Barnett and Abdoulaye Meite after the two were rushed back into action after respective injuries and a lack of training.
"The two centre-halves who played today have both been injured and that was their first game back together," Mowbray revealed.
"Meite played at Hull last weekend but he didn't play in midweek and hasn't trained.
"You try and ease them back into football.
"Leon's trained two days in just under a month.
"Yet, you make those decisions because you feel their attributes will handle the opposition better.
"Ultimately, they didn't.
"Sometimes, your selections for games work and other times they don't.
"Today, pretty basic balls into our box - long diagonal balls - caused us problems.
"We didn't deal with them."