Manchester United goalkeeper David de Gea feels he is in the form of his life after helping Spain to a 1-0 Euro 2016 qualifying win over Ukraine on Monday.

De Gea endured a difficult start to the 2015-16 campaign as he was temporarily dropped in favour of Sergio Romero at Manchester United when his future at the club was uncertain due to strong interest from Real Madrid.

He was reinstated as United's number one after his future was resolved, though, and has since put in a string of impressive performances, with the game against Ukraine his latest eye-catching display.

"I'm in the best form of my career. I always try and do my best. Things worked out well and the important thing was to win the game," he told reporters.

"I always give my all and against Ukraine luck was on my side too. This is the way forward.

"For a goalkeeper, all saves are important, but if I had to choose one, maybe the stop with my feet in the first half with the game tied at 0-0. I'd opt for that one as my favourite."

De Gea got the nod for Spain ahead of Iker Casillas, who was the man between the sticks in last week's 4-0 win over Luxembourg, but there is no animosity between the pair.

"Iker congratulated me on the performance," he said.

"He's been an elite player for so long, so it's natural he wants to help me along, of course.

"I just want to be at the top of my game to make the decision for Vicente del Bosque as difficult as possible as to who should start at Euro 2016."

De Gea recently signed a new contract with United until 2019, with some claiming his new deal contains a clause that would allow him to leave if Real Madrid meet a set fee.

However, the United keeper was in no mood to go into details when questioned about the existence of such as clause.

"You should ask Jorge [Mendes, agent] that question; he's the one who pays attention to those details," he said.