– After the Pole great performance in Wimbledon, where he reached his 1st GS SF ( getting a career high of #17 in consequence) , it’s quite fair to say that he’s surpassed fellow youngstar Grigor Dimitrov as the most exciting prospect for the future ( Dimitrov stands at #29). We will draw some comparisons:
Age: Both are 22, but Janowicz was born in 1990 [ he is from November] and Dimitrov in 1991 [ in May], so Dimitrov is 6 months younger.
Height: Janowicz stands at 6′ 8″ [ 203 cm.] while Dimitrov is at 6′ 2″ [ 188 cm. ].
Both are right-handed.
Career High Ranking: Janowicz has the edge with his #17, Dimitrov was as high as #26 in May.
ATP wins : Dimitrov has the edge here, with 70 wins compared to Janowicz 40 ( though the pole has just 29 losses compared to Grigor’s 68).
Top-20 wins: Dimitrov has 4 ( vs #1 Djokovic in Madrid 2013, #10 Tipsarevic in Monte-Carlo 2013, #13 Raonic in Brisbane 2013 & #7 Berdych in Miami 2012), while Janowicz has 9 ( vs #16 Almagro in Wimbledon 2013, #9 Gasquet in Rome 2013, #8 Tsonga in Rome 2013, #18 Querrey in Madrid 2013, #20 Simon, #9 Tipsarevic, #3 Murray, #15 Cilic & #19 Kohlschreiber in Paris 2012, his magic week).
Masters 1000 best performance: Janowicz has clearly the edge, with a F in Paris and a QF in Rome, while Dimitrov best result is a QF in Monte-Carlo.
Grand Slams best performance: Again Janowicz wins, with his Wimbledon SF’ compared to Dimitrov R3 in Roland Garros.
Both have 1 final and 0 titles, Dimitrov one being in Brisbane ( lost to Murray) and Janowicz one in Paris ( lost to Ferrer).
So, stats reveal us that Janowicz is way ahead at the moment, despite Dimitrov greater hype and much better junior career. What strikes me about the pole is his ability to shine on big tournaments ( like in Paris 2012 or in Wimbledon this year), while Grigor still struggles to do well on big occasions ( bar in his great match vs Djokovic in Madrid this year, a real masterclass from him). I still firmly believe though, that in few time Dimitrov will be up to Janowicz level, the bulgarian has a great game, and if he works hard on his return we could be seeing him in the top-10 in one or two years.
My bet for them at the end of the year is:
Janowicz will end the season in the Top-15, with another big result to come.
Dimitrov will end close to Top-20, but will still lack something to make it.
I also think that one of them, or both will snatch a title this season, more likely in the indoor season.
Good luck to both!
Tennis Factor 
Dimitrov has a more complete game. Janowicz’s court positioning needs work but he has a bigger serve than Dimitrov. I think that Janowicz may do better this year but Dimitrov will have a better career, he’s simply more talented.
Yeah, I think Grigor will have a better career, it’s just a matter of fullfilling his talent [ I hope he does better than Gasquet, who had the same hype and never really live up to the expectation ( though he’s a solid #9 right now I initially believed he could go further). Still, I think Janowicz will prove to be really competitive, he’s got a lot of tools ( specially that huge serve) and I think his game can click on all surfaces when playing well, so he can be a solid Top-10 IMO in 1-2 years.
Gasquet did much more than Dimitrov at any stage of their careers: he defeated Federer in 2005, had won some tournaments and was ranked higher than Dimitrov at the same age. Yet Gasquet has not won an ATP 500 tour event let alone a Masters or a Major.
Dimitrov needs a lot of matches and careful, deep coaching. I see someone like Federer or Nadal as players who can solve their own problems – even at young ages, but players like Dimitrov, Murray, Djokovic as ones who need deeper coaching to fix inherent problems with their game. Dimitrov’s current coaching set up is fantastic.
Janowicz isn’t liked on the tour, Gilles Simon words. It’ll be be interesting to see how this aspect progresses.