Coca-Cola is hoping to dramatically boost its position in the energy market with the first energy shot under its Relentless brand.

The 50ml Relentless Shots are said to provide the same energy as half a can of regular 500ml Relentless, with 80mg of caffeine as well as vitamins B6 and B12 among the ingredients. They will be available in grocery retail outlets from this week, positioned beside tills.

The location of the shots in-store was vital to drive sales and consumer awareness, said Relentless brand manager, Dave Leslie. "Proximity to other impulse categories in-store is key to ensure success of this launch. With this in mind, we have developed sales-ready case packaging, as well as a selection of merchandising and point-of-sale material, to educate consumers on the proposition."

The functional nature of shots had "a much wider appeal to a bigger audience" than larger-volume energy drinks, he said, despite soaring sales in the larger-volume category, up 5.8% to £535m in the past year (Nielsen).

The launch will be supported by a multi-million-pound marketing campaign kicking off later this year across various media.

Relentless Shots are the latest in a line of energy shot launches this year, with brands such as Quick Energy, Focus 5-hour Energy and Powershot all having debuted since February.

This week also saw the launch of Pocket Rocket, containing 134mg of caffeine per 50ml shot, compared with an average 80g in other shots.

"Although we are a small company, our product outshines competitors on the market as it is a stimulant shot rather than simply an energy drink in a small bottle," said Pocket Rocket co-founder Tony Pannett.

Meanwhile, Red Bull claimed its super-sized 473ml can, which was launched just four months ago, had become the top-selling 500ml can energy drink, having overtaken Monster and Relentless to achieve £1.3m in sales over the past year [Nielsen].