MENDOZA, Argentina (AP) — Kurtley Beale has been dropped from the Wallabies squad for the last Rugby Championship test against Argentina, sparking speculation that his omission had more to do with a lapse in conduct than form.

Beale was involved in an argument with an Australian Rugby Union official during the team's trip from South Africa to Argentina after last weekend's loss to the Springboks in Cape Town.

Australia coach Ewen McKenzie revealed in the hours leading up to his squad announcement that he'd referred the matter to the ARU's integrity unit, and told local media it was a "complicated" matter. Beale remained in Argentina with the squad and was available for selection, while a female staffer returned to Australia. No details were released, although the ARU released a statement saying its investigation would be completed by the end of next week.

Hours later, Beale's name was missing when the 23-man test squad was unveiled for Saturday's test in Mendoza. McKenzie opted for a 6-2 split of forwards and backs on the reserves bench — not for the first time — and Rob Horne was selected the utility backline role on the bench ahead of Beale. There was no comment on Beale, who played most of the second half in the 28-10 loss to South Africa last week. He was one of the stars of the New South Wales Waratahs' Super Rugby winning lineup this season, but has been off form since starting at flyhalf in the first two tests of the Super Rugby series — a 12-12 draw at home and a 51-20 defeat to the All Blacks in Auckland.

Former skipper James Horwill and backrower Scott Higginbotham were recalled to the starting lineup to replace lock Rob Simmons and No. 8 Ben McCalman, who were both injured in the loss to South Africa.

Australia's starting backline remained intact, with Matt Toomua passing concussion protocols to retain his spot in the centers.

Beale was one of three backs on the bench last week but lost his place when McKenzie elected to take an extra forward replacement into the match as cover, anticipating a grinding battle up front.

The 47-cap utility back has missed matches due to disciplinary issues before, and spent weeks on the sidelines last year after a dispute with his then Melbourne Rebels teammates on a Super Rugby tour to South Africa.

His absence leaves only scrumhalf Nic White and Horne as reinforcements for the backline. Giant lock Will Skelton and Matt Hodgson return to the 23-man squad, along with uncapped backrower Jake Schatz and hooker Josh Mann-Rae.

"We recognize the need to have enough strike-power in the forwards to get us through the back end of the game, especially after such a physical encounter against South Africa followed by a difficult period of travel," McKenzie said in a statement. "That only leaves two spots for the backs, and we believe in this instance the combination of Nic White and Rob Horne will provide us with the best balance given the physicality we expect in this match.

"In the end, we feel the combination of the entire bench will offer us the vigor and intensity we need in attack and defense in the later stages of the game."

Australia goes into the test with two wins, a draw against New Zealand and away losses to the All Blacks and Springboks. Argentina is winless in the tournament but with injuries and off-field distractions upsetting the Wallabies preparation, the Pumas pose a big challenge on home soil. The Australians beat Argentina 32-25 at the Gold Coast last month, taking a 29-13 lead then holding off a strong finish from the Pumas.

___

Australia: Israel Folau, Adam Ashley-Cooper, Tevita Kuridrani, Matt Toomua, Joe Tomane, Bernard Foley, Nick Phipps; Scott Higginbotham, Michael Hooper (captain), Scott Fardy, James Horwill, Sam Carter, Sekope Kepu, Saia Fainga'a, James Slipper. Reserves: Josh Mann-Rea, Benn Robinson, Ben Alexander, Will Skelton, Jake Schatz, Matt Hodgson, Nic White, Rob Horne.