Cristiano Ronaldo is coming off a hat trick in his last La Liga match. Reuters

Champions League heats up this week, with several prominent clubs facing intriguing foes in group play.

Real Madrid look to build off their 1-0 victory against Dinamo Zagreb earlier this month, when they host Dutch club Ajax at Santiago Bernabeu on Tuesday.

Los Galacticos got some much-need scoring with their 6-2 victory over Rayo Vallecano on Saturday off Cristiano Ronaldo's hat trick. Prior to that victory, Jose Mourinho's squad had shown signs of weakness in their attack after a scoreless draw with Racing Santander, and a 1-0 loss to Levante.

Their Dutch competitors aren't exactly flying throught the competition lately, either. Ajax is currently in third place in the Eredivisie, and have three draws in their last three matches against Lyon in Champions League, and against rivals PSV and FC Twente in league play.

Manager Frank de Boer has a squad led by young defenders Jan Vertonghen and Gregory van der Wiel, who will be responsible for containing Real Madrid's collection of attacking midfielders and forwards.

Ajax have some talented attackers of their own, including young Serbian Miralem Sulejmani, and new addition Kolbeinn Sigporsson, of Iceland, who has already scored five goals in six matches. Kolbeinn previously played for AZ, where he scored 15 goals in 32 games, and has scored four goals in seven appearances for Iceland.

But it will be the Ajax midfield that will be under the most scrutiny. De Boer will need Christian Eriksen to be a catalyst for the attack, and Theo Jansenn to create goal-scoring opportunities for a club that may not have many chances on the road.

Ajax will likely play defensive, but that strategy can't last 90 minutes, as Mourinho's squad is capable of jumping on the board in the early going.

Real Madrid's attack is among the best in the world. Ronaldo, who was booed in Zagreb and went scoreless in his last Champions League match, needed stitches after an ugly tackle by Jerko Leko went unpunished, and would like to respond with improved play against Ajax.

I do not understand, said Ronaldo. I'm sad because the referees say they will protect the most skilled players. Some players can't get close to me, so they kick me.

As important as Ronaldo is to Real Madrid, Mesut Ozil has proven to be among the most dynamic central midfielders in the game today. The German playmaker entered Saturday's game as a sub in the 29th minute, so he will be in good shape for Tuesday's match.

Mourinho will need Sami Khedira to step up on Tuesday. Khedira only played 31 minutes against Rayo Vallecano, and the defensive midfielder will be needed with a makeshift central defense. Veteran defender Ricardo Carvalho suffered a severe concussion last week, and Pepe remains injured, as well. It will be up to Khedira to prevent Ajax forwards from penatrating into the box.

The Santiago Bernabeu can be an intimidating place to play for opponents, and Real Madrid should feel comfortable against an Ajax club that might be in awe of their surroundings, and their talent-rich hosts.