The Portuguese has netted only twice in Europe so far in 2016-17 and has some work ahead if he is to finish as top scorer in the continental competition this time around
Cristiano Ronaldo is back on form in front of goal. After something of a slow start to the season with Real Madrid, the Portuguese was back to his best with a hat-trick in the 3-0 win at Atletico on Saturday. In the Champions League, however, he has some catching up to do.
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The 31-year-old has reached double figures in the Champions League in each of the last five seasons, leading the scoring charts with a record 17 strikes en route to La Decima in 2013-14 and then 16 as Madrid claimed the trophy again last season.
That tally included 11 in the group stages as Ronaldo ran amok against Malmo (six goals in two games) and Shakhtar Donetsk (five in two), plus strikes home and away to Roma in the last 16 and a hat-trick in the quarter-final second leg versus Wolfsburg as Los Blancos overcame a 2-0 deficit from the first match.
This time around, though, the goals have been harder to come by. The Portuguese scored a free-kick in the 2-1 win over his former club Sporting CP at the Santiago Bernabeu in September and also struck early on in the 2-2 draw away to Borussia Dortmund later in the same month. But that, so far, is all - two goals in four matches.
It is not a bad return, but below his usual ratio and surprisingly, the three-time Ballon d'Or winner was unable to score either home or away against the group's weakest side, Legia Warsaw.
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Not that he hasn't been trying: in four full matches, Ronaldo has had 29 attempts on goal, with nine on target, but just two goals. In that time, he has also assisted three for his team-mates.
In the meantime, Lionel Messi has scored seven already for Barcelona. The Argentine bagged a hat-trick in the 7-0 win at home to Celtic in September and another treble in the 4-0 thrashing of Manchester City last month, as well as converting in the 3-1 defeat away to Pep Guardiola's side at the beginning of November.
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Messi missed Barca's other game, the 2-1 victory away to Borussia Monchengladbach, through injury, so his seven strikes have come in just three matches and a total of only 12 attempts.
It is already a greater return than his six goals in seven Champions League games last season and he is well on course to beat the 10 he netted en route to the trophy in 2014-15 - and perhaps even the 14 he managed in 2011-12.
Since then, it is Ronaldo who has been scoring at a superior rate in the continental competition (with 55 goals in the past four editions to Messi's 32). But this time it is the Portuguese playing catch-up and if he wants to end as top marksman in the Champions League for a record sixth time, he had better start scoring soon.