Wallabies lock Will Skelton admits turning his back on a crack at the Rugby World Cup to re-sign with Saracens was the toughest decision of his career.
The 26-year-old is poised to ink a new two-year deal with the powerhouse English club, who take on Irish giants Leinster in a highly-anticipated European Champions Cup final on Saturday (Sunday 0200 AEST).
Skelton will go head-to-head with fellow former Wallaby Scott Fardy in the European final this weekend.
His new deal comes despite some late efforts at persuasion from Wallabies coach Michael Cheika, who was keen to regain Skelton as an option for an Australian second row that's struggled for consistency.
The former NSW Waratahs lock, who once tipped the scales at 140kg, has been in outstanding form this season having shed 21kg in 18 months.
Skelton moved to the UK after Cheika lost patience with his lack of fitness and dropped him following the 2016 Spring Tour.
Under the leadership of Saracens coach Mark McCall, Skelton has thrived in a squad brimming with international stars including Maro Itoje, Billy Vunipola, Owen Farrell, Schalk Burger and Liam Williams.
However, with just 18 international appearances to his name, Skelton is a long way short of the 60 required under Rugby Australia's Giteau's law - which permits overseas-based players to be selected for the Wallabies.
"I had some chats with Cheik at the start of the year and my manager has spoken to him a lot," Skelton told AAP.
"He was trying to get me back home and there were some (Super Rugby) offers but it is difficult because I've agreed to stay here.
"There's still a few bits and pieces to to nut down but I am close to signing a new deal here.
"It was a massively difficult decision given the World Cup is this year but if the rules change in the future I'll always put my hand up to play for Australia."
Skelton had to bide his time in his first season with Saracens after McCall told him no uncertain terms that unless he lost weight he'd never fulfil the potential he showed when he debuted for the Waratahs as a 19-year-old.
"Will's been a revelation since he came over here," McCall told AAP.
"But he'll be the first to admit he's been a bit a slow burner.
"He's always been a huge talent and able to bring something to a team that other players can't, not only because of his size but his skill set as well.
"But what we needed from Will was for him to have a bigger impact in games and the only way to do that was for him to lose some weight.
"He's done that through his own single-mindedness.
"The club love him, the coaches love him and the players love him, and we want to keep him."
Leinster, the current European champions, stand in the way of Saracens' quest for a third title in four years in a match that will be played at Newcastle United's St James' Park.
Fardy will line up for the Irish side and Skelton is looking forward to locking horns with his ex-international teammate.
"Fards' always tough, he is a great player and great bloke, as well," he said.
"He's gone over there and added value to Leinster and help make them successful.
"It will be a great challenge and I am looking forward to it - these are the games every rugby player wants to play in."
Defending champions Leinster believe they will need a special display to beat Saracens and win an historic fifth European title in a clash of the continent's heavyweights on Saturday in Newcastle.
The Dublin-based side know they will have to be at their best at St James' Park, the home of Newcastle United football club, to stop London outfit Saracens from avenging that loss and becoming three-time winners of Europe's premier club rugby union title.
"We are well aware we are going to have to raise our game," said Leinster and Ireland lock James Ryan.
"I think they are better than last year."
Saracens are seeking a third European title in four years, having triumphed in 2016 and 2017, and McCall was adamant his English champions would be a more formidable force that they were in last season's Dublin quarter-final.
"We'll be in a much better state physically and mentally," said McCall, a former Ireland centre.
"We were in a different place then. England had just had a very poor Six Nations, Ireland had just won the Grand Slam and we were missing some key players," he added.
McCall, whose side overpowered Munster 32-16 in this season's semi-finals, looks set to have all of his star names available this time, England prop Mako Vunipola having been passed fit following an ankle problem.
Much is likely to depend on the dominance that Vunipola and his brother, No. 8 Billy, can help Saracens gain up front -- and on whether fly-half Owen Farrell can prove a more influential orchestrator than his opposite number, Johnny Sexton.
World player of the year Sexton was short of his best after being rushed back from injury for Ireland in this year's Six Nations but was close to his most influential form with a man-of-the display against Toulouse in the match semi-final.
Sexton is the all-time leading points scorer in Champions Cup finals, with 63 from Leinster's four previous wins.
Farrell is the top points scorer in this season's competition, with 79. The England outside-half is also the third top points scorer in history in all stages of the tournament, with 767 - behind Ronan O'Gara (1,365) and Stephen Jones (869).