July 27 (Reuters) - Teck Resources Ltd Chief Executive Officer Don Lindsay will step down after 17 years at the helm, the Canadian miner said on Tuesday, as it posted a quarterly profit that beat estimates on upbeat prices for steelmaking coal.

Lindsay, who will step down by end-September, will be replaced by Jonathan Price as CEO, while Harry Conger has been appointed president and chief operating officer.

The Vancouver-based miner needs a leader who will be around and accountable long-term as it shifts its focus to copper from carbon, Lindsay said, on his 71st and final post-earnings call on Wednesday.

"And I clearly wasn't going to be the one to be around," said the 63-year old top boss.

Teck also posted a second-quarter adjusted profit of C$3.25, highest on record, above analysts' expectation of C$3.20 a share, as per Refinitiv data.

Steel production and demand for steelmaking coal was strong through most of the second quarter before market conditions began to weaken last month, Teck said.

Average price of steelmaking coal in the reported quarter jumped 215% to $453 per tonne from year-ago levels, before exiting the quarter at $300 per tonne, the miner added.

Still, the company added that global steelmaking coal prices are affected by reduced downstream steel demand as weakening auto production and global inflationary pressures weigh on market sentiment.

Teck flagged labor issues as its 'single-biggest challenge' with its massive QB2 copper project in Chile seeing absenteeism of 10% during the quarter.

Teck cut its annual steelmaking coal production outlook to between 23.5 million and 24 million tonnes, below previous forecast of 24.5 million to 25.5 million tonnes, citing workforce challenges experienced in the first half of the year.

Inflationary woes increased Teck's quarterly operating costs by 14% year-on-year, of which about half relates to a 75% increase in diesel costs.

($1 = 1.2868 Canadian dollars) (Reporting by Akriti Sharma, Arunima Kumar and Ruhi Soni in Bengaluru; Editing by Sherry Jacob-Phillips)