The trio have all been hired from the organisation's coaching pool and will work under head coach Ken Eriksen.

An immediate target is Tokyo 2020, where women's softball and men's baseball will return to the Olympic programme for the first time since Beijing 2008.

Berg is a triple Olympic gold medallist, having played for the winning American sides at Atlanta 1996, Sydney 2000 and Athens 2004.

She also won silver in Beijing when Japan won the gold medal.

Flowers also won gold in Athens and silver in the Chinese capital.

"Congratulations to all four coaches on this much-deserved selection as an assistant coach for our 2020 women's national team," USA Softball chief executive Craig Cress said. 

"Their qualifications alone speak volumes to their ability to lead and guide athletes in their journey to gold. 

"It's also extremely special for us to have two Olympians on our coaching staff who can share invaluable experience and knowledge on what the members of the 2020 team can expect."

Six teams will contest the softball tournament at Tokyo 2020, with the US joined by hosts Japan, Italy, Mexico, Canada and Australia.

"The addition of assistant coaches Laura Berg, Howard Dobson, Tairia Flowers and Heather Tarr is a bonus for our athletes," said Eriksen. 

"Their combined knowledge, experience and communication abilities is a tremendous asset for our team in its efforts to get better every day. 

"With Olympic Games experiences amongst the staff, I feel very honoured to have these four great people join us."

Berg, currently head coach at Oregon State, added: "I'm so thankful for the opportunity to work with this incredible team and coaching staff."