"It puts a bit of a spanner in the works," said coach Danny Kerry. "I can't make final decisions until I know what the medical team says."
Kerry will select his 16-woman line-up for the Olympics, plus two reserves, from a squad of 28, with an announcement expected on 18 May, but the injuries hampered his ability to begin finalising his squad.
Defender Cullen, a set-piece specialist, turned her ankle in scoring her second goal against Argentina and required crutches after the game, while striker Danson came off the field in agony after clattering her left arm in a collision with a defender.
Britain's coach expressed concern at Argentina's approach to Sunday's game at the Olympic Park's Riverbank Arena, saying: "There was stuff going on out there.
"For those of you who play, watch and coach hockey a lot, you know exactly what's going on. I've probably already said too much."
Argentine players were involved in both incidents, although neither warranted any action from the on-field umpires.
Danson has a case history of shoulder injuries, including one the year before the Beijing 2008 Olympics, but later
that she "will be right as rain in no time".
"We'll have to wait for the medical team to assess them," said captain Kate Walsh.
"At Bisham Abbey, where we train, we have the Olympic medical institute so all the best rehab know-how in the world is on our doorstep.
to be told via group email from coach Danny Kerry at 0800 BST one morning this week, with official announcement at London Stock Exchange on 18 May
selection takes place in mid-June. Players can elect to hear the news by text, call, email or face-to-face. Some will receive "unofficial pats on the back" beforehand, says coach Jason Lee
"I'm sure they are going to be fine - there's still quite a bit of time. Alex, pre-Beijing,
rolled her ankle in a warm-up game
and was back for the Games. They are both quick healers and two of the fittest players in the team."
Simon Mantell is also a casualty of the test event, missing two of the GB men's games after fracturing a bone in his foot during Thursday's group game against India.
Mantell was due for treatment on Monday and the team's coach, Jason Lee, said selection might be delayed while Mantell and longer-term absentee Matt Daly are given time to return to fitness.
"We haven't got a definitive date for selection at the moment because one player in particular, Matt Daly, has a long-term injury and no predicted date for his return," said Lee.
"Matt's played at every major tournament for the last seven years and has a goalscoring record of one in three. I think he deserved the opportunity to be selected.
"The selection date has been left open to see if there's an opportunity for him to get in, and the same applies to Simon Mantell as a consequence of his injury. We're aiming to do it by mid-June.
"Simon will be back in hockey by mid-July - that might be too late."
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