Rafael Nadal battled through three hard sets to beat Grigor Dimitrov in the second round at the 2015 Swiss Indoors in Basel on Wednesday.

Ivo Karlovic produced an impressive comeback as he downed second seed Stan Wawrinka 3-6, 7-6(2), 6-4 and booked his spot in the second round. Karlovic's serve let him down in the opener, and he went a set down to hand Wawrinka the momentum, but he came surging back to pull off a surprise victory in three. 

Fourth seed Kevin Anderson went through to the next round after beating Borna Coric in two sets 6-3, 6-2, while Marin Cilic downed Switzerland's Marco Chiudinelli 6-3, 7-6(3).

Here's a look at the day's results from Switzerland and a review of the best action.

Recap

Nadal made a poor start to his match against Dimitrov, as he went 2-0 down after conceding an early break. However, the Spaniard proved his resilience to bounce back to 4-4, and a second break of serve saw him close out the set 6-4.

It was even worse for Nadal in the second as he went 4-0 down to the Bulgarian, and this time he did not have enough to fight his way back into the set.

It was an enthralling encounter, with both players producing some fabulous tennis to keep their opponent guessing and breaks of serve coming thick and fast.

Nadal was again broken early in the third set, but he levelled for 2-2 soon after. The world No. 7 found the power and touch to better Dimitrov 6-3 in the decider and claim victory. 

Wawrinka pounced early on Karlovic's unusually poor serving to claim a valuable break in the fourth game of his match to go 3-1 ahead. He almost handed the break back at 5-3 as he served for the set, but he eventually went 1-0 up having forced the game to deuce.

The crowd favourite produced a brilliant forehand pass to break again in the first game of the second set, but Karlovic then finally seemed to find his rhythm.

The world No. 23 clawed back some of the momentum as he upped his intensity, and his brilliant net play allowed him to break back and draw level at 3-3 before he won the inevitable tiebreak to force a decider.

Wawrinka was very much on the back foot, and he was broken to go 1-0 down in the third. He simply could not get a look in on Karlovic's serve, and a hold to love in the 10th game of the third set handed the 36-year-old a deserved victory in two hours.

Cilic was made to work hard for a 90-minute victory against Basel-born Chiudinelli, but the seventh seed eventually came through in straight sets.

The 2014 U.S. Open winner was clinical on his serve in the opener, not giving up a single break-point opportunity and taking one of the two he was offered to claim the set.

The second set was a tougher task, although Cilic again did not give an inch on serve. Chiudinelli was able to force a tiebreak, but he could not take the match into a decider.

Anderson looked impressive in his routine victory over Coric. His touch at the net was a particular highlight, per TennisTV:

Early breaks in both sets saw him to a comfortable victory in just over an hour, and the South African will now face America's Donald Young in the second round.

Full results and updated schedule for the men's draw are available via the ATP website.