Alonso seems happy on his first day of training with his new team-mates
Spain midfielder Xabi Alonso has completed his £30m transfer to big-spending Real Madrid from Liverpool after passing a medical on Wednesday.
The Reds revealed on Tuesday that a deal had been struck but added the terms would remain confidential.
The 27-year-old Spanish international joined Liverpool from Real Sociedad in August 2004 for £10.5m.
"It's a very happy day for me. It's an important step in my career to come to a club like Real Madrid," said Alonso.
"I'm very happy to be part of this club and I was very excited for this day to arrive.
"It's the best opportunity for me to develop as a footballer."
Alonso played 210 games for Liverpool, and he admitted that he was sad to leave the club's fanatical Anfield support behind.
It is a personal challenge I felt is necessary for my football career
Real Madrid midfielder Xabi Alonso
"I am very grateful to Liverpool fans, they were very warm during my five years," said Alonso.
"It will be really difficult to match their appreciation. I really enjoyed those five years.
"But a few months ago I took that decision as I thought it was the right moment to find a fresh challenge, to look for a new club.
"That's when Real Madrid came along. Luckily a deal has been done and I'm very happy.
"It is a personal challenge I felt is necessary for my football career.
"I felt it was right so I looked for a change, for a new experience, and when Madrid came in, that's when I decided to come back to Spain."
Technical director Jorge Valdano said the capture of Alonso would signal the end of Real Madrid's buying spree which has now seen them spend over £200m.
"Before the start of the pre-season, the coach Manuel Pellegrini told us it was necessary to strengthen two positions: the defence and the midfield, and that is what we have done," he said.
Alonso becomes the second Liverpool player to join the Spanish giants after full-back Alvaro Arbeloa's £3.5m switch to the Bernabeu in July.
Real, under the guidance of returning president Florentino Perez, have embarked on an ambitious rebuilding programme this summer.
Cristiano Ronaldo arrived from Manchester United in a world record £80m deal, Brazilian playmaker Kaka was bought from AC Milan for £56m and Real have also spent £30m to sign France striker Karim Benzema from Lyon.
In addition, defender Raul Albiol was signed from Valencia as Real look to build a squad capable of challenging for honours at both home and abroad.
Rivals Barcelona completed a clean sweep of domestic trophies in Spain last season, while Real have failed to progress beyond the last 16 of the Champions League for the past five seasons.
Alonso's transfer to the La Liga club brings to an end Real's long pursuit of the Spanish international.
It is believed Real returned with an offer of £30m that could rise to £34m, depending on Alonso's success in Spain.
He will join former Liverpool goalkeeper Jerzy Dudek at the Bernabeu, leaving only Steven Gerrard and Jamie Carragher from Liverpool's 18-man squad that won the Champions League in 2005.
Alonso and Dudek were both part of the side that dramatically fought back from 3-0 down against AC Milan to win the trophy in a penalty shoot-out, Alonso scoring Liverpool's third and equalising goal on 59 minutes.
Liverpool manager Rafael Benitez had tried to sell the Spanish international last summer as he looked to fund a move for midfielder Gareth Barry from Aston Villa.
However, Alonso did not want to move and a deal for Barry eventually fell through, with Alonso going on to play a key role as Liverpool finished second in the Premier League.
"I respect Rafa and thank him for the opportunity he gave me," added Alonso.
"The goodbyes were quite brief, everything happened very quickly and I didn't have time to say goodbye properly.
"I want to return to say goodbye to my team-mates and Rafa. As everything was very quick I hardly had time so as soon as I can I will say goodbye as I should have done."
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