JONNY May says England have a couple more gears to move through as they target a 2-0 series triumph over Argentina.

The 27-year-old Gloucester wing is bracing himself for a backlash from the Pumas after they were pipped 38-34 in the first Test in San Juan on Saturday.

But he insists England are in no mood to let up after they stepped up preparations for the next clash in Sante Fe with a rigorous training session at the San Isidro Club, 14 miles north of Buenos Aires.

"I feel this weekend they're going to be better and we're going to have to be better as well," said May, who will win his 27th cap on Saturday.

"I still think there's a couple more gears in this side, especially seeing as how many new guys we've got. We are getting used to it and developing in every session and every day.

"Today was probably our biggest hit-out of the week and our physical day. We always train hard, aiming to train above match intensity so it was a hard session.

"We have got better every session as a squad so that is good preparation.

"The aim is to train that hard and not get hurt, and recover as well. The emphasis is huge on recovery here we have ice baths, massage, stretching... so that is how we manage to train at that intensity and also get prepared for a Test match.

"It is great training. It is fatigue, it is unstructured and it works you physically and mentally and it also brings the team together as well.

"When you are under that physical stress and unstructured play under fatigue it gets you ready for the hard matches you play.

"On Saturday there were some long phases of play and some tough bits but it is not by chance that we win in those last plays of the game. We train so hard to prepare for those times."

May is now close to regaining peak fitness following a 10-month lay-off with the knee injury he sustained in an Aviva Premiership match in December 2015.

He says his visit to Olympic champion Michael Johnson's academy in Texas is beginning to pay off as he can now reach 23mph in sprint training.

"I have been running over 10 metres per second recently which is good," May said. "I have been looked after this week, not because of my knee, but so I can be fresh for next week.

"I couldn't even run a year ago. Considering my injury, I have exceeded my expectations of what I thought I would achieve this year.

"Eighteen months is when they say it is as good as new and I am 15 months now. Although I don't notice it getting better, it probably is.

"I worked so hard on it. After this tour it will be the first break I have had since the World Cup because last summer I did not take a day off to get my knee right.

"I am looking forward to having a real good game this weekend and then having a good break."

England coach Eddie Jones will announce his team for the second Test after they fly to Santa Fe on Thursday and it looks likely he will make at least two changes.

Former captain Chris Robshaw is set to win his 56th cap after missing the opening game with an ankle injury while fly-half or centre Piers Francis is poised to make his first start after coming on as a substitute in San Juan.

Francis, who turns 27 next Tuesday, joined the England camp on the eve of the tour from Auckland, where he plays for the Blues in Super Rugby, and missed the chance to play against the Lions in order to make his Test debut.

Jones will check on the fitness of forwards Nathan Hughes and Joe Launchbury, who undertook their own fitness work during the team's contact session run at San Isidro.