Real Madrid midfielder Xabi Alonso expects there to be plenty of highs and lows between now and the end of the season.
Jose Mourinho's side lead Barcelona at the top of La Liga by three points and have a game in hand, with the teams set to meet early next month.
While Real have lost just one league game all season and qualified for the Champions League knockout stages with ease, Alonso is refusing to get too carried away.
"This season we have taken a step forward," he told Marca. "We have a fantastic defence, with a great attack and we do not stop.
"Collectively we are working very well and we all benefit from that. We'll see how it goes this season. Sure we take plenty of joy, but also some disappointment, for sure. There is a long way to go.''
Alonso revealed Cristiano Ronaldo did not train on Wednesday for a second day as a result of an ankle sprain and contusion suffered in a challenge with Luis Perea during Saturday's 4-1 win over Atletico Madrid.
"He has not trained with the team, but hopefully he can get to the game with Sporting Gijon (at the weekend)," Alonso said. "Perea's tackle was hard but luckily not as serious as it could have been. We accept that football is a contact sport, sometimes you get it, sometimes you give it .''
Alonso would not be drawn on the yellow card issued to Barcelona's Gerard Pique in their 4-0 win over Rayo Vallecano on Tuesday which ensures he will not miss El Clasico.
Pique was booked seven minutes from the end for time-wasting, provoking some controversy. However, Alonso would only say: "It is not for me to talk about this issue - this is another club and another player.''
Alonso joined Real from Liverpool in 2009 for a fee of £30 million and has become a key player for them.