Broad, who has been hampered by a heel injury and a virus during the current tour, has taken no wickets for the loss of 157 runs in two matches and could be dropped in Kolkata to make way for Steven Finn.
Finn took four wickets yesterday in an England Performance Programme game as he recuperates from the thigh strain that has prevented him from playing since the first warm-up match.
Saker said of Broad: “There’s a little bit of an issue, there’s no doubt about it. He hasn’t bowled as we would have liked, and he would be the first to admit that.
“He’s not the first bowler to come over here and find it hard. The great fast bowlers have had success over here. Stuart’s probably not a great yet. He has to learn ways to become great. It’s a learning time for him.
“During my tenure as bowling coach, I haven’t had too many players down in confidence and form. This is when I have to come to the party. I hope I can do some stuff over the next few days that can help.”
Batsman Ian Bell, who missed the second Test due to the birth of his child, is set to return in place of Jonny Bairstow, while Saker preached caution over Finn’s fitness.
“He’s got that X-factor,” he said. “If he gets through unscathed and bowls well, his name will definitely be talked about for selection.”