Southeastern Asset Management Inc., owner of one of every 10 shares in Chesapeake Energy Corp., said its growing more bullish on the natural gas producer as Chief Executive Officer Doug Lawler trims costs.

Southeastern said in a letter to its shareholders today that the outlook for Oklahoma City-based Chesapeake has improved because Lawler “has made substantial progress since taking the helm” in June.

Lawler’s “capital discipline and operational effectiveness will reward shareholders,” the Memphis-based asset management firm led by O. Mason Hawkins said in its letter today.

Hawkins teamed with billionaire activist investor Carl Icahn last year to remove Chesapeake co-founder and shale-gas pioneer Aubrey McClendon and replace him with Lawler, a former Anadarko Petroleum Corp. executive.