Tammy Beaumont rides luck to realise her 2005 dream with Ashes Test ton

"Just pump your legs fast… and if you have to dive, dive." That's all Tammy Beaumont told herself as she sprinted for a second run that would take her to a maiden Test century in the penultimate over of a tough but hugely rewarding day.

She had spent a day-and-a-half fielding, mostly at close quarters, as Australia reached a massive first-innings 473 before becoming only the second woman behind Heather Knight, her captain and batting partner for a large part of her knock, to score a hundred in all three international formats.

Unbeaten on 100 at the close, Beaumont also had the satisfaction of keeping her side in an Ashes Test that looked to be headed firmly Australia's way earlier on the second day. And she said she was no stranger to close encounters when big milestones presented themselves.

"I think I should have been run out in my first ODI hundred," Beaumont said. "I should have been run out on 99 hitting it straight to a fielder and running. For me, there was an opportunity there and it was probably the fastest one I ran in the day but hey, who cares? I'm in.

"I knew I could get there. I knew it was going to go my end and I had a good chance of getting there. If I don't dive in then you know I don't think I'm close. I'm pretty much an idiot, always got grazes on my elbows because I'm always on the floor, but if it's not tight I don't dive."

Beaumont's innings, which included a century stand with Knight and an unbroken 67-run partnership for the third wicket with Nat Sciver-Brunt, helped England to 218 for 2 on a batting friendly surface at Trent Bridge with their opener in fine touch, having scored 201 not out in last week's warm-up match.

England still trail by 255 and Beaumont said the end result would ultimately determine where this innings ranked in her international career, which began in 2009 and now spans 210 matches across formats.

"It feels pretty good," said Beaumont, who a year ago lost her place in England's T20 side for the Commonwealth Games and T20 World Cup. "There were probably moments where I thought I wasn't going to face enough balls to get there tonight it's put the team in a good position going into tomorrow so hopefully we can bat long tomorrow and that's what it's all about at the minute.

"For me, it's all about whether I contribute to the team so if we win this Test match and we go on to win, I think it will be right up there. Let's wait and see. It's great to tick it off and yes, as a kid, I dreamt of scoring an Ashes Test hundred. Pretty much since 2005, that probably has been my goal but as I've gone on, for me, it's about contributing to the team."

She enjoyed a stroke of luck on 61 when she hit legspinner Alana King into her boot and the ball hooped to Phoebe Litchfield at short leg, but the catch wasn't awarded and Australia didn't review.

"I knew I hit it, I knew it hit my foot, I didn't know if it hit the floor as well," Beaumont said. "But not my decision to make and not mine to overturn or anything like that. I think it's hard to tell when it hits your foot whether it's also hit the ground at the same time. So I guess I got lucky with one. But then again, I've probably had a couple of unlucky decisions in the last month or so in regional cricket, so I guess the luck came at the right time."

Knight admitted Beaumont "had got away with one" but was impressed with her opener's performance, which she described as "really powerful".

"I thought, 'Oh, that's close.' I chatted to Tammy in the middle and she was like, 'Yeah, I was out,'" Knight told Sky Sports. "She's got tiny feet as well, I don't know how she's managed to hit that up. But yeah, obviously they didn't review it and Tammy got away with one there.

"I'm pretty sure she was desperate to get it [her hundred] before the end of play… really proud of her. It's hard work being out in the field for so long but I think the concentration and the skill level that she showed was outstanding."

Annabel Sutherland, who scored an unbeaten 137 for Australia off the back of another century in a warm-up against England A, made a case for promotion from No.8, although she was happy to slot in wherever required as part of "a pretty solid lineup".

"It's pretty special," Sutherland said. "I'm not sure it's quite sunk in yet. "It's something you dream of growing up, just to pull on the Baggy Green, but to do that job for the team yesterday and today it was pretty cool and I had great support at the other end. The main thing was just getting in there and spending time out there, that was what was required for the team and I was just happy to play my part.

"Tammy and Nat in particular batted exceptionally well but in saying that we created seven or eight chances, so I think given we're 260 ahead, still well and truly ahead in the game. If we can we can start well tomorrow morning then that'll put us in good stead and hopefully we can sharpen up a little bit in the field so we can take those chances. You never know, there's still three days to go and lots of time in the game."