London - Having made a slow start to his Liverpool career, midfielder Adam Lallana believes he was "trying a bit too hard" to impress at Anfield after joining from Southampton.
The 26-year-old, who signed from Premier League rivals Southampton for around £25 million following this year's World Cup, has made 12 appearances for Brendan Rodgers's side after being hampered by a knee injury.
"I always knew it was going to be difficult settling in, especially with the injury," Lallana told the club's website.
"Playing for a new club the size of Liverpool and having Champions League football - you need to be tough mentally.
"I was so desperate to do well, maybe trying a bit too hard to impress, not doing things that I'd normally do, thinking about things maybe a bit too much. You can't always expect to be at your best straight away."
Lallana played a crucial role in a Southampton's eighth-place Premier League finish last season, and the creative midfielder admitted he had been frustrated by 11th-placed Liverpool's slow start to the campaign.
"When you've been away for seven or eight weeks, the pitch feels a bit different when you step back on it for the first time," he said.
"It's a case of getting your head down, working hard and doing the things that have made you successful before to get back to a level where you can affect matches.
"Gradually, the more games I've played and the more minutes I've accumulated, my form has improved and I'm getting closer to the levels I was at last season for Southampton. There's still an improvement to be made but I'm getting there."