He is now backing Long to rediscover the goalscoring form which saw him net in the double figures for Saints in the 2015/16 season.
“It’s good for any of our strikers to get off the mark,” Bertrand told the Daily Echo. “He worked very hard on Friday and got what he deserved.
“If you look at his commitment, it’s never in question. He just needs to get the rub of the green sometimes and he got that against Liverpool.
“Hopefully, he can go on and keep that form going now.
“People are always going to talk but as long as you stay mentally strong and believe in your abilities then you can do your talking on the pitch.”
Long’s Liverpool goal was only his second of the season.
Given how threadbare Southampton’s striking options are in the ongoing relegation battle, Saints fans will be hoping Long can find his shooting boots.