Danny Care says missing out on selection for the British and Irish Lions affected his performance for Harlequins against Wasps on Sunday.
Care, 34, had been told he was under consideration for the 37-man squad.
But he missed out as Conor Murray, Ali Price and Gareth Davies were selected by boss Warren Gatland.
“I found it really hard to get up for it mentally because Thursday I didn’t get the nod,” Care told the BBC Rugby Union Weekly podcast.
“It was a massive game for us and I wanted to play well, and personally I didn’t have a brilliant game.
“I didn’t start very well and I think I had a little bit going on in my head.
“Mentally it can grate on you. So I was a little bit off it and I had to have a bit of a word with myself at half-time and then I think I snapped out of it in the second half.”
It was the fourth successive tour for which Care was told he was under consideration for only to be left out.
“It doesn’t get any easier. It’s the hope that kills you because I wouldn’t have dreamed of being in contention,” added Care, who has been at Harlequins since 2006 and has won 84 England caps.
“Then because we’ve been playing quite well and I’ve personally done alright and I got the letter I thought ‘Maybe this is the year that I can be a Lion’.
“I had mates texting me all the time, sending me articles, sending me odds saying ‘Mate, you’re 4/5 to go – you’re on the plane’ and I’m like ‘Lads I haven’t heard a single thing’.
“I thought it would be those three because they played in the Six Nations and unfortunately I didn’t have that opportunity to play in the Six Nations, so understandably they’ve gone with three lads that have played well and played in big games.
“I don’t know how many scrum-halves got a letter. I don’t know whether I was sixth or seventh on the list of scrum-halves or fourth.
“I don’t know whether I really ever stood a chance and that’s the worst thing about it – you’ve got no idea.”