Kroger’s board voted unanimously to elevate chief operating officer John Myers to chief executive officer effective April 1. Myers will succeed Rodney McMullen, who led the grocer for 15 years and will remain as executive chairman through year-end.

The announcement triggered a 4.2% gain in Kroger’s shares during early trading, its largest one-day jump since January. Trading volume nearly doubled the 30-day average as investors priced in potential strategic shifts.

Myers will begin a staged handover with McMullen providing oversight on long-term initiatives, including supply chain modernization and loyalty program expansion. The new CEO will assume full operational control at the start of the second quarter.

Investors expect Myers to accelerate digital and delivery services growth, building on Kroger’s existing partnerships with tech platforms. Analysts say his background in operations could drive further cost efficiencies and margin improvements.