Jos Buttler has urged his England players not to get sucked into a state of desperation this week regarding net run-rate as they try to resurrect their T20 World Cup defence from a perilous position.

England go into the games against Oman this Thursday, and Namibia on Saturday, needing two substantial victories to keep alive their hopes of reaching the Super Eight stage. Even then this may be in vain, with ­Scotland, direct rivals for a top-two spot, playing Australia in the final game of Group B.

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Able only to match Scotland’s five points – provided Australia do their Ashes rivals a favour and win in St Lucia – Buttler has wargamed some possible routes to correcting England’s current NRR of -1.8. By the same token, the captain is mindful of obsessing about this to the detriment of performance, not least given the obvious in-game variables.

“I don’t think it’s shit or bust quite yet,” Buttler said, as England resumed training at the Antigua ­Recreation Ground in St John’s.

“I think it’s quite clear what we need to do and how we need to play. We have to be aware of [NRR], but not be consumed by it. If we try and do that bit first and forget about ­trying to win the game and lose, then we’ve got no chance anyway. We see it as a challenge, we’re not daunted by it; an opportunity to do something special.”

After a slightly tetchy first press conference in Barbados last week, Buttler had a sunnier disposition ­on Tuesday, comfortable with the ­criticism that followed their 36-run defeat by Australia and stating that, as an armchair supporter of other sports – one who sometimes shouts at the TV – he understood the frustration.

Buttler, not scheduled originally to speak before deciding to step up, said: “At times it feels tough and you have difficult moments or a couple of hours awake at night. But that’s part of the enjoyment of [captaincy] and quite addictive as well, trying to find solutions, ways to get the best out of your players, get the best out of yourself, and ways to get to where you want to be.

“I think there’s a lot of realism that we have only had one and a ­quarter games. It’s very easy to say we’re in a tough position, but we haven’t played loads of cricket. We were outplayed by Australia, and had one game [against Scotland] rained out. There’s still lots of confidence in the group.”

In fairness, his players did appear upbeat as they began the session at the Old Rec with a curious game ­involving certain players whipping others with what appeared to be pool noodles. Even in its slightly dilapidated state these days, a ground that once shook with calypso rhythms, and where Brian Lara twice compiled world-record Test scores, made for an evocative setting for England to blow off the cobwebs from their ­rickety start to this tournament.

Both matches this week will be staged at the Sir Vivian Richards ­Stadium – the out-of-town venue built with Chinese soft-power money for the 2007 World Cup – with the Old Rec last used in 2009; the ­hastily arranged third Test between West Indies and England after the second game, at the ground’s replacement, was ­abandoned after 10 balls because of to a ­dangerous, sandy outfield.

Andrew Flintoff, here as a con­sultant coach, is the one survivor in the current setup from that match and had reason to be cheery. As England went through their drills, ­Buttler ­having given little away ­regarding selection for the Oman game, his 16-year-old son, Rocky, was named in the under-19s squad to face Sri Lanka in three youth one-day internationals at home that will begin this month.