Bamford admits career has stalled over the last 18 months

Striker Patrick Bamford said he has not developed as much as he would have liked over the last 18 months but hopes his fortunes change following his transfer from Chelsea to relegation-threatened Middlesbrough this week.

The 23-year-old joined six different clubs on loan during his five years at Chelsea, most recently making six substitute appearances for Premier League Burnley this season.

He has never scored a Premier League goal despite also having loan spells at Crystal Palace and Norwich City last season.

"The last 18 months have been really frustrating. There were times when I was upset driving home from training. I was thinking 'I need to do something here' as I wasn't enjoying it," he told Sky Sports.

"My development has stalled because I haven't played as many games, but I still learnt things in training. I've changed my approach to training, which is important. I've also toughened up mentally. It's been hard.

"It's been tough but I'm ready for this next challenge."

Bamford spent the 2014-15 season on loan at Middlesbrough when they were in the second tier. He enjoyed a successful first stint at the Riverside Stadium, scoring 19 goals as the club reached a Wembley play-off final.

Bamford left Chelsea without making a senior appearance for the Premier League leaders and said his departure was a bitter-sweet moment.

"My dream was to play for Chelsea -- maybe I was bit naive," he said.

"I still have that dream. You never know what's going to happen in the future but for now, even though I was sad to leave, it was one of the happiest days of my life. Now I've got to help Boro push on and see how far we can get."

Middlesbrough, who are 16th in the table, host 12th-placed West Ham United on Saturday.