Shane Watson's greater experience of England and his capacity to bowl some of the kinds of spells Ryan Harris might have delivered for Australia appears set to squeeze him into the first Test team ahead of Mitchell Marsh, as part of a bowling attack the assistant coach Craig McDermott still calls the best in the world.

While the younger Marsh has turned plenty of heads with his bold batting on tour, the Australian team's decision-makers still feel Watson offers more security as a bowler. Without Harris, the control Watson can offer with miserly spells and swing of both conventional and reverse varieties will be even more highly valued.

McDermott, on his first Ashes tour since leaving the 1993 trip early due to a life-threatening twisted bowel, said that while Marsh's bowling was improving, Watson still had something of an edge. "With the fourth seamer only bowling 10-15 overs tops depending on how they're bowling and how the other guys are going, his control is excellent," McDermott said. "He's a lot more experienced and has been around for a long time so you'd expect his control and everything else to be better.

"Mitch is still developing. He's got some pace back; the No. 1 thing we were chasing for from him was to get some speed up. Him obviously being nervous with his injuries throughout the summer in Australia and wanting to stay on the paddock made him back off a little bit I think. Now he's our No. 1 man over the 2km time trial and all that sort of stuff he's got his fitness back, he's lost some weight and he's got his pace back up.

"He's actually swinging the ball nicely now, he bowled a lot better in the second innings in Essex than the first innings and also Canterbury. So considering he hasn't had a lot of four-day cricket bowling it's a work in progress but he's coming on nicely."

Side by side: Mitchell Marsh and Shane Watson net together, but who will get the nod? Getty Images

While Australia's order of preference for pace bowlers has been shaken up considerably by Harris' exit, it remains likely that Peter Siddle will miss out on a place in the team unless the selectors plump for the unlikely option of choosing four fast men in addition to Watson. At the very least, Siddle's quality bowling in Canterbury, Chelmsford and the Cardiff nets is keeping Mitchell Starc, Josh Hazlewood and Mitchell Johnson on their toes.

"It's disappointing for him but we've got to find someone else to do the job he does and I'm sure four of the guys we've got are quite capable of doing that," McDermott said. "Peter Siddle's bowled very well in the last couple of games, the other guys are getting back into their work, and Jono's bowling quicker here than he has for a while I think and swinging the ball nicely. So those four frontline guys are all in the mix and if we don't play four it'll be a tough selection call.

"Everyone who's been through the World Cup and to the IPL in particular took a bit of time to get back into their work. Jono's arm path has got a bit better over here, a bit higher and he's got his seam in a better position, and he's just got a real spring in his step at the minute, so that's good for us and hopefully not good for the Poms.

"Starcy and Josh basically had two and a half weeks off from game time, so just took a little bit of time to get back into their rhythm and bowling. They both bowled very well in the second innings in Essex, so we're pretty happy with their preparation, and Sidds bowled well in both games and his pace got better as well."

Two of the vagaries of English conditions are the swing extractable from the Dukes ball and the smaller dimensions of the grounds, meaning runs can accrue quickly if bowlers get too greedy in their search for a "glory ball". McDermott espoused the virtues of balance, and did not mind the thought of a new, more aggressive England going out searching for deliveries bowled in the fourth stump channel.

"We've got to bowl our good lines and lengths which we did in Australia in the last series, and we stuck to our game plan," he said. "You don't want to attack too much, but you need still to attack. Our game with our bowling and fielding is to be attacking and aggressive, that's the Australian way and the only way we know how to play.

"The boys this morning were swinging the ball a lot. So it's making sure you don't get too greedy and using the crease to get your lines correct and make the batsmen play. If we do get a lot of swing we can use the crease to maximise that, and that's pretty important for our attack and certainly Sidds is one who uses the crease well. The other guys do as well, but he uses it as good as anyone.

"We've got a bowling attack that suits pretty much every facet of cricket, whether it's a reverse wicket or a wicket that turns with seven left-handers is good for Lyono, and obviously if the wicket's got green grass on it and goes through a bit, even if it's a bit slower, the wicket's still going to seam if it's got some grass on it. Our attack is really well placed for whatever we get dished up."