Four rivalries could flourish in 2014

December is the downtime of the tennis season, when players train for the New Year that dawns Down Under at the Australian Open and observers dream of the adrenaline rush rivalries can produce.

Compelling rivalries can be the tennis equivalent of a film franchise that continues to crank out successful sequels. Competitive character, contrasting styles and personalities, and the daring to strike under pressure can all conspire to push the plotline of a match in adventurous directions.

Blockbuster rivalries pulsate with stars the world knows on a first-name basis: Rafa vs. Novak and Serena vs. Vika. Engaging rivalries can create a euphoric buzz and the craving for rematch.

We’re rooting for four potential rivalries in particular -- two featuring Top 10 players and two between players with Top-10 potential -- to flourish in 2014.

No. 2 Victoria Azarenka vs. No. 6 Petra Kvitova

Head-to-head: Kvitova leads 4-2

These aggressive baseliners both arrived at the 2012 Australian Open semifinals with a shot to seize the world No. 1 ranking, and while Azarenka won the title to secure the top spot then defended her Melbourne crown last January, Kvitova has been busy battling health and consistency issues.

Surprisingly, these two Grand Slam champions have not faced off since Kvitova defeated Azarenka, 7-5, 4-6, 6-3, in the 2011 WTA Championships final. This matchup intrigues because it features two immaculate ball strikers who can dictate play from the baseline. It pits Azarenka’s sniper return against the left-handed Kvitova’s sometime lethal serve.

In 2013, Azarenka led the WTA in return games won (54.8 percent), while Kvitova was third on Tour in aces (250). Three of their six meetings have come in Grand Slam tournaments and though the 6-foot Kvitova can be more explosive, the 6-foot Azarenka is usually more exact.

Azarenka is a more ruthless front-runner, a more tenacious competitor, she’s won more titles (17 to 11) and has reached at least the semifinals of all four majors. But Kvitova possesses more variety, is comfortable from all areas of the court and can be more dangerous on all surfaces: She’s won titles on hard court, grass and clay.

The Czech can be streaky and prone to the mid-match malaise, though. Kvitova must compete with more consistency and play more efficiently in early rounds to reignite this rivalry. She played 37 three-setters in 2013, while the more commanding Azarenka went the distance just 15 times last season.

An encouraging sign for Kvitova: She was 10-1 in her final 11 three-setters of the season and reached at least the semifinals in four of her final five tournaments, including the WTA Championships.

No. 11 Simona Halep vs. No. 12 Sloane Stephens

Head-to-head: Stephens leads 2-1

Remember when some insisted the retirements of Martina Hingis and Justine Henin marked the end of women shorter than 5-10 winning Grand Slam singles titles and the start of the WTA's amazon age?

Toss the tape measure aside and try this fact on: Since the 5-9 Serena Williams won the 2009 Australian Open, 16 of the last 20 Grand Slam titles have been won by women standing 5-9 or shorter. The success of Halep and Stephens reinforces the fact that timing, technique, court coverage and all-surface acumen still matter more than size.

The 5-6 Halep rocketed up the rankings from No. 47 at the end of 2012 to a year-end rank of No. 11 in 2013, earning WTA Most Improved Player of the Year honors. The 5-7 Stephens showed flashes of elite form, knocking off a hobbled Serena to reach the Australian Open semifinals and advancing to the Wimbledon quarterfinals, losing to eventual-champion Marion Bartoli.

Both are bound for the Top 10, and each exhibits what the other aspires to achieve. Halep was at her best in WTA tournaments -- winning six titles on three different surfaces -- but was underwhelming in Grand Slam play, losing in the opening round of both the Australian Open (to Stephens) and Roland Garros.

Stephens has played her most inspired tennis in Grand Slam tournaments, but can look downright disengaged in WTA events: The 20-year-old American has yet to reach a WTA final.

Both can crack the first serve and both concluded 2013 parting with coaches: Halep split from Adrian Marcu and Stephens, who had been coached by the USTA's David Nainkin, is now working with Paul Annacone, who formerly coached Roger Federer, Tim Henman and Pete Sampras. Halep has shown a sharper court sense and competitive instinct, but Stephens, one of the fastest women in the game, may have a higher upside if she can clearly define her style and play with more passion.

No. 8 Stanislas Wawrinka vs. No. 10 Jo-Wilfried Tsonga

Head-to-head: Tsonga leads 3-2

Two things usually happen when these two meet: Dynamic tennis erupts and the match goes the distance.

At the 2011 French Open, Wawrinka roared back from a two-set deficit to beat Tsonga. In their French rematch a year later, Tsonga halted another Wawrinka comeback with a 6-4, 7-6 (6), 3-6, 3-6, 6-4 triumph in a match that spanned four hours spread out over two days, with both guys splattering winners across the red clay.

Because both are strong servers -- Tsonga was fourth on the ATP in service games won (88 percent), Wawrinka was 11th (85 percent) -- breaks can be scarce. They were born 20 days apart and their meetings can come down to tactical imposition.

Wawrinka wants to work Tsonga over in backhand exchanges, because Stan’s one-hander is a much more reliable and penetrating shot than Jo’s two-hander. Tsonga, whose forehand is his best shot, tries to wield that weapon against Wawrinka, who hits his forehand flatter and can be streakier off that side.

Tsonga tends to play closer to the baseline, but both can close at the net and Wawrinka has applied his all-court skills more effectively working with coach and former French Open finalist Magnus Norman. When pushed out of position, both men are prone to indulging their shot-making urges and play the down the line drive.

No. 21 Jerzy Janowicz vs. No. 23 Grigor Dimitrov

Head-to-head: None

What do you get when you mix power, finesse, volatility, agility, eye-popping shot-making on the move and mind-numbing shot selection at crunch time? Magic and mayhem.

You know pop culture has infiltrated the sport when you see two guys with the freaky athletic ability of Janowicz and Dimitrov pull off shotmaking so audacious, it looks like it came straight from the mind of an over-caffeinated video geek on an Xbox binge.

Both men had break-out moments in 2013. In just his fifth Grand Slam main draw, Janowicz reached the Wimbledon semifinal to become the first Polish man to advance to a major semifinal. Dimitrov, who upset world No. 1 Novak Djokovic on clay in Madrid, rallied for a 2-6, 6-3, 6-4 victory over No. 3 David Ferrer in the Stockholm final in October to win his first ATP title, becoming the first Bulgarian in the Open Era to win an ATP crown.

The 6-8- Janowicz looks like he’s leaping off a step ladder when serving -- he hit 30 aces in three sets against Nicolas Almagro at Wimbledon -- but he’s not a mindless baseline basher.

Janowicz’s bold two-handed backhand, flair for the angled drop shot, imposing size and agility, and volatile and wacky temper -- an Australian Open meltdown during which he repeatedly raged "How many times? How many times?" inspired a YouTube hip-hop remix -- make him as unsettling as an evening spent slam-dancing with sumo wrestlers.

Dimitrov is an enchanting talent because he can flash of shot-making magic on the move from virtually anywhere on court, and the contrast between his explosive topspin forehand and the biting slice of his one-handed backhand can be a jarring combination. Dimitrov’s all-court skills and athleticism are dazzling; his atrocious major results -- he’s failed to surpass the second round in 12 of 13 Grand Slam starts -- are disconcerting.

"I think Dimitrov has a huge upside. If he stays healthy, he has a live arm, huge serve, he moves well," James Blake told me last month. "Looks like he's comfortable hitting any shot. Just a matter for him of putting it all together. If I had to say one [young] guy that has the game that actually excites me, it's Dimitrov. Milos Raonic is the most uncomfortable to play, but I don't get quite excited watching a guy serve 25 aces and win a match 6 and 6."