Atrocious shot selection from skipper Manoj Tiwary and his deputy Sudeep Chatterjee saw Delhi take control of the proceedings, restricting Bengal to 273 for 7 on day one of the Ranji Trophy semifinals.
On a pitch where there was a good carry but no demons, Bengal batsmen batted comfortably till they committed harakiri in the final session.
Bengal were comfortably placed at 200 for 3 when a couple of innocuous deliveries from left-arm spinner Manan Sharma (2/37 in 13 overs) changed the complexion of the match.
Having added 68 for the fourth wicket, Tiwary looking set on 30, decided to give Manan the charge.
It was bowled with a flatter trajectory and Tiwary charged out. His intention was to loft the spinner over mid-on but what he played was a chip shot. Himmat Singh took the easiest of catches at mid-on.
If that wasn't enough, Chatterjee, who was on 83 played an even more irresponsible shot in Manan's very next over which was the 65th of the innings.
A rank half-tracker saw Sudeep rock back trying to smash one through covers which substitute Unmukt Chand plucked inches above the ground.
Chatterjee's 162 ball innings had 10 fours but he lost out on a golden opportunity to prove his mettle on a big stage with national selector Sarandeep Singh in attendance.
He also shared 78 runs for the third wicket with Writtick Chatterjee (47) with the latter being adjudged leg before off Vikas Tokas.
More importantly, the momentum shifted in favour of Delhi once Manoj and Chatterjee were gone.
Anushtup Majumdar (32) was graceful till he was at the crease with some lovely flick shots.
However, Navdeep Saini (2/45 in 17 overs)'s raw pace exposed Majumdar's weakness against fast bowling. An off- cutter came in a shade at a good pace and Anushtup couldn't get his bat down to leave his off stump dislodged.
Saini had also got Abhimanyu Easwaran (4) in the first session with a quick delivery.
Kulwant Khejroliya's (1/57 in 17 overs) bouncer tactic also paid dividends when B Amit tried the ramp shot which was pouched by Manan at deep third man.
"I knew Manoj loves to hit spinners over the top. But I didn't know that he would give me the charge so soon. About Sudeep, I can say there are times when even good balls don't get us wickets. So I won't mind if that ball got me one," Manan said after the match.
With Wriddhiman Saha ruled out due to viral fever and body pain, Shreevats Goswami (19 batting) was persisted with.
He survived a barrage of short-pitched deliveries and will look to take his team to a reasonably respectable score in the 350 range tomorrow.
Bengal 273/7 in 87 overs (Sudeep Chatterjee 83, Writtick Chatterjee 47, Manan Sharma 2/37, Navdeep Saini 2/45) vs Delhi.