The centerpiece of ATP action this week is clearly the 500 event in Rotterdam, which vies with Dubai for providing the most entertaining tennis of February.  Half of the top-10 men have entered, leaving several notable talents unseeded as dangerous floaters.

Top half:  Fans of Juan Martin del Potro must have breathed a sigh of relief when the Tower of Tandil announced that he would attempt to defend his Rotterdam title.  Bounced in the second round of the Australian Open, del Potro struggled with a left wrist injury there that will merit attention this week.  His draw has done him few favors, for Australian Open quarterfinalist Grigor Dimitrov appeared to turn a corner in Melbourne and will be eager to build on that breakthrough.  Even before that quarterfinal tilt, last week’s Montpellier champion Gael Monfils could catch del Potro off guard in one of the draw’s most exciting first-round encounters.  A 12-0 start to 2014 against opponents other than Rafael Nadal may have given Monfils the confidence that he needs to challenge a rusty member of the elite. Less impressive lately, Ernests Gulbis is still not someone whom Dimitrov or del Potro can afford to overlook.

Another man who suffered from injury at the Australian Open, Tommy Haas appeared to have recovered from shoulder pain with a finals run in Zagreb.  Also like Del Potro, Haas faces an explosive first-round opponent in Fernando Verdasco.  But the Spaniard has left his best tennis several years behind him, failing to revive his career after a surprise quarterfinal run at Wimbledon last year.  Another of the surprises at the All England Club, Jerzy Janowicz, has his prime years ahead of him.  The indoor hard court should showcase his massive first strikes against Haas or world No. 7 Tomas Berdych.  Having charged to the semifinals at the Australian Open, Berdych should feel equipped to master the challenge of a shoot-out with Janowicz after hitting through counterpunchers such as Gilles Simon.

Bottom half:  Not many ATP draws feature three Dutchmen in the same quarter.  Far from a tennis power, the host nation of Rotterdam handed out wildcards to this trio of home hopes.  Dutch fans must have frowned to see them prepare to cannibalize each other, or more likely play into the hands of Richard Gasquet.  The world No. 9 can face no pre-semifinal opponent more intimidating than Mikhail Youzhny.  And the Russian squandered a substantial lead against a lucky loser in his Zagreb opener, suggesting that he will not bring his best form here.

The fourth and final Rotterdam wildcard went to a man somewhat more famous than those who received the other three.  Weathering the challenge of winning on clay in Davis Cup, Andy Murray continues to find his rhythm slowly but surely in his return from back surgery.  He reached the Australian Open quarterfinals with minimal match practice, so he should not find his soft Rotterdam section too stern an obstacle.  A quarterfinal clash of top-10 men could pit Murray against Jo-Wilfried Tsonga, working through a coaching transition as he tries to reclaim his belief against the best.  Even on fast courts, that matchup always has favored Murray, but this surface will give Tsonga his best chance.  Fresh from a fourth title at his home tournament in Zagreb, Marin Cilic looks to play the spoiler’s role.

Sometimes the most intriguing names at small tournaments are not those of the bold-faced seeds with byes but the unseeded players on the lines between them.  This is largely the case in Memphis, downgraded from an ATP 500 to an ATP 250 tournament this year. 

Top half:  The only top-20 man in the field, defending champion Kei Nishikori holds the top seed and momentum from lifting Japan to the Davis Cup quarterfinals.  That historic weekend contrasted with the adversity suffered by sixth seed Sam Querrey under the American flag.  Querrey must rebound quickly from losing both of his singles rubbers to Great Britain, including a five-set collapse to an opponent outside the top 150.  The indoor hard court in Memphis should suit him better than the clay in San Diego, but his second-round match intrigues no matter the opponent.  There, Querrey will face either the surging Bjorn Phau, a semifinalist in Zagreb last week, or stagnating compatriot Ryan Harrison.

Like the United States, Australia tasted defeat in Davis Cup last weekend.  But Lleyton Hewitt and Nick Kyrgios, both members of that team, can draw on brighter January memories to inspire them.  Hewitt won a title on home soil at Brisbane, upsetting Roger Federer, while Kyrgios notched a main-draw win at the Australian Open.  The elder Aussie can look forward to a rematch of his late-night Melbourne thriller against Marcos Baghdatis, who looks to reward tournament organizers for his wildcard.  So does Kyrgios, set to clash with home hope Tim Smyczek.

Bottom half:  Knowing what to expect from Donald Young is nearly impossible these days.  That in itself marks a step forward for Young, who regularly underachieved for most of his career.  He showed promise by reaching the third round of the Australian Open, but a dismal meltdown at that stage and a rout in Davis Cup left him in a position similar to Querrey.  Helping Kazakhstan stay alive in team competition, Mikhail Kukushkin has played more tennis on indoor hard courts recently than most of the others in his section.  Fourth seed Yen-Hsun Lu hovers near the edge of the top 50 after reaching a final in Auckland after a startling upset over top-five opponent David Ferrer.

The Australian subplot from the top half trickles into the bottom half with Marinko Matosevic and Matthew Ebden.  Ace machine Ivo Karlovic might arrive mentally flat after his exertions in Zagreb, highlighted by a historic 44-ace display.  Rarely does a modern ATP match feature serve-volleying on both sides of the net, so his first-round meeting with Ebden will be worth a look for purists.  Also ready to rush the forecourt, last year’s finalist Feliciano Lopez looks to set up a rematch with Nishikori in the final.  Offense always has thrived in Memphis, which has crowned recent champions and runners-up ranging from Andy Roddick and Milos Raonic to Radek Stepanek and Jurgen Melzer.  This trend should give Jack Sock some hope as he aims to refine his raw weapons and build his ranking.

This week contains something for everyone in the ATP.  As fast-court specialists salivate over Rotterdam and Memphis, grinders and dirt devils look forward to Buenos Aires.  Like last week’s tournament in Vina del Mar, this 250 clay event attracts players mostly from southern Europe and South America.

Top half:  World No. 5 David Ferrer has spent much of the last several months losing to journeymen whom he normally dismisses with ease, such as Dmitry Tursunov, Joao Sousa, Daniel Brands, and Yen-Hsun Lu.  A setback on his favored clay would ring alarm bells even more loudly than those hard-court defeats, so Ferrer has much to prove during a swing that he has dominated before.  Still, the Buenos Aires draw offers him a comfort zone designed to build his confidence.  Fellow clay specialists from Albert Montanes to Juan Monaco are essentially lesser, similarly aging versions of Ferrer.

Nothing but futility has come of Nicolas Almagro’s 14 attempts to conquer Ferrer. Having held a match point in 2012 and served for the match three times in 2013, Almagro will face a massive mental obstacle if they meet in the semifinals.  He does bring momentum from a strong week in Chile, his first tournament since returning from a shoulder injury.  The quirky but slumping Alexandr Dolgopolov might pose the only real test for Almagro before Ferrer.

Bottom half:  In contrast to Almagro, another Spaniard endured a surprising setback in Vina del Mar.  Halted in his first match there, Tommy Robredo looks to rebound against one of the ATP’s emerging talents.  Pablo Carreno Busta turned heads by reeling off a long winning streak on the Challenger Tour last year and reaching a clay semifinal in Portugal.  He has lost four of five matches in 2014, however, perhaps sinking into a sophomore slump.  A maiden titlist last year, Joao Sousa stands in a similar position of struggling to build on his breakthrough.

Last week’s Vina del Mar final pitted top-20 man Fabio Fognini against unseeded Argentine Leonardo Mayer.  This pair could clash again in the second round of Buenos Aires if they can bring their momentum from Chile.   Yet another Spaniard, Marcel Granollers, faces a challenging opener as the fifth seed against Slovenian talent Aljaz Bedene.