At the company's capital markets day on Tuesday, Antofagasta guided production of around 725,000 tonnes for 2023, and around 700,000 tonnes for 2024.
These estimates missed Jefferies' expectations by 6.5% and 11.3% respectively.
Jefferies was also unconvinced by the company's plan to grow copper output by 20% by 2026, to 900,000 tonnes. "We are sceptical about this target ever being reached as we expect production from Anto's existing mines to decline and the lead time for the Centinela expansion to be longer than the deck indicates," Jefferies said.
The growth in output is contingent on the construction of a second concentrator at its Centinela, which will need to be approved by the board at the end of 2022.
But despite its operational headwinds, Jefferies retained its "buy" rating on the company.
"The bears will point to this production outlook as a reason to sell the stock," Jefferies said. "We would point to this as a reason to buy copper miners as it adds to the evidence of downside risk to expectations for copper supply and corresponding upside risk to the copper price."
"It is not just Anto that will miss consensus production forecasts, in our view. This will be an industry-wide phenomenon that should lead to higher than expected prices."
Analysts have been suggesting the disappointing performance of copper miners in 2021 is only likely to get worse as water shortages and aging mines continue to weigh in 2022, even as demand for the meatal booms.