He struggled against the pace attacks of New Zealand and Australia in 2015 and was dropped after two Ashes Tests, before earning his place back previous year.
Meanwhile Broad, a veteran of 102 Tests, insisted he was fully fit for the first of a four-match series against South Africa after his participation was called into question by a foot injury.
After winning the ODI and T20I series against the Proteas, England will miss the services of Chris Woakes and Jake Ball as the two are yet to recover from injuries.
The 31-year-old spent two weeks on the sidelines before returning to play in his county's Royal London One-Day Cup final win over Surrey at the weekend.
South Africa's team huddle including captain Dean Elgar top second left facing camera during the nets session at Lord's London Tue
"I think he's very aware of his game, he's gone away and worked very hard at it and he looks very in control, and found ways of putting pressure back on the bowlers and making sure he doesn't waste scoring opportunities". It's pulled up really well. The guys are raring to go and really looking forward to tomorrow'.
"I've been playing county cricket since early April so I've had quite a lot of red-ball cricket, so I am not concerned about the workload and it was great to have the intensity of the Lord's final to put the body to the test", Broad told Sky Sports.
"Liam is going to play", Root said on Wednesday ahead of his first test since he succeeded Alastair Cook as England captain in February.
When asked if his batting would be a boost for England Dawson replied: "The way England have played in the last few years you know they have batted deep and obviously that helps but as I said let's wait and see what team they decide to go with". "He was announced a long time ago and now he has the chance to put things into place".
"South Africa have a really good record in England and are a very unsafe team". South Africa have a really good record in England and are a very unsafe team...
AAA Says Gas Prices Have Decreased Compared To Last July 4th
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