Trevor Bayliss has talked up England’s chances of claiming an Ashes victory against a flawed Australia side this winter provided they can arrest the epidemic of dropped catches witnessed against West Indies and one he described as “terrible”.

“We are not going over there to make up the numbers. We are going to leave here with a view to win. It is as simple as that,” said the England head coach, who was in bullish mood after witnessing two series wins from two in Joe Root’s first summer as captain.

Bayliss did accept his No3-ranked team remain incomplete, not least with three batting spots still to be nailed down. But he was encouraged by the “fight” and “character” shown when bouncing back from Test defeats at Trent Bridge against South Africa and at Headingley against West Indies. “Our opposition in the Ashes are probably far from being stable too,” he said.

One area that left Bayliss bitterly disappointed, however, was in the catching, with 16 chances going down in three Tests against West Indies alone. Since his appointment in 2015 the Australian has put a high price on fielding, including some changes to technique, yet the recent results have dipped alarmingly.

Bayliss said: “The fielding always concerns me. The catching has been terrible. Some of the drops were quite easy and to me that is usually down to concentration. We are certainly not going to go [to Australia] and win anything dropping that many.”

Among the positives for Bayliss has been Root’s leadership itself but the pair remain divided on where he should bat in the order. The move down to No4 has come at the captain’s insistence and not affected the runs – Root averaged 60.7 across the seven matches and equalled the record of 12 successive Tests with a score of 50 or more – but Bayliss still wants him one higher. “I’d always have him at No3,” he said. “He’s asked the question over the last few Tests. It is an option that he gets back there and I think he will end up at No3 at some stage. He’s by far our best player and personally I think that’s where the best player should bat.”

That Root was beginning to consider the matter in recent weeks suggests Tom Westley, the incumbent at first drop, is in need of a strong finish to the county season with Essex. The 28-year-old averaged 24 from nine innings with one half-century but at least signed off from England duty with an unbeaten 44 in Saturday’s fourth-innings run chase at Lord’s.

Greater encouragement was forthcoming for Westley’s fellow newcomers Dawid Malan and Mark Stoneman, not least the latter whom Bayliss described as a “tough cricketer” at the top of the order and one whose “game is in good order”. The Surrey opener made one half-century, at Headingley, in his six knocks and appears likely to travel to Australia.

Bayliss said: “[Stoneman] is calm around the changing room and has a good knowledge of the game. He copped a couple of good deliveries during this series and he didn’t let it worry him, he just came out and made runs in some difficult circumstances. Malan missed out early and there was a bit of pressure on him, then he got a couple of 60s since so is very much in the running.

“[The three batsmen] have shown that they are good enough but are they good enough for long enough? Are they tough enough? Especially for an Ashes series. We will be discussing other players that we have had in the team over the last 12-18 months but these three guys it will be hard to go past them, put it that way.”

This debate among the selectors will take place during the final round of County Championship fixtures that begins on 24 September, with the three batsmen made fully available to their counties for the remainder of the campaign along with the seamer Toby Roland-Jones.

Chris Woakes will also be able to play for Warwickshire against Essex before joining up with the one-day squad next week.

Jimmy Anderson and Stuart Broad have seen their seasons end, however, with the latter due for further scans this week to assess the problem with his left heel that has nagged throughout the run of seven Tests in just over eight weeks. The former, meanwhile, heads into the break as the world’s No1 bowler, having overtaken India’s Ravi Jadeja at the top of the rankings with 39 wickets at 14.

On how Anderson’s form will translate to Australia, given the pitches and the Kookaburra ball being less conducive to lateral movement, Baylisss said: “It will swing early and there is a day-night Test too [in Adelaide] but the main thing there is your consistency and accuracy. He never goes for a lot of runs but this season, in particular, he has got the ball in the right areas a lot more than our other players.”

Bayliss also said that a full-time replacement for the bowling coach, Ottis Gibson, may not be in place until next summer.