BERLIN, GERMANY - JUNE 20: UFC women's strawweight champion Joanna Jedrzejczyk of Poland celebrates after defeating Jessica Penne of the United States in their women's strawweight championship bout during the UFC Fight Night event at the O2 World on June 20, 2015 in Berlin, Germany. (Photo by Josh Hedges/Zuffa LLC/Zuffa LLC via Getty Images) Josh Hedges/Zuffa LLC

Joanna Jedrzejczyk needed all five rounds to turn away her latest challenger as the incumbent strawweight champion won a unanimous decision over Valerie Letourneau in the UFC 193 co-main event.

While many predicted that Jedrzejczyk would upend Letourneau in a lopsided fight, the American Top Team product gave the champion a battle, especially in the opening rounds until she finally started to fade late.

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Letourneau was able to take advantage early with a takedown on the champion while showcasing her size and power, but it was short lived once the fighters worked back to the feet.

Jedrzejczyk measured her opponent in striking range and unleashed a front kick that blasted Letourneau directly in the face, stunning her for a moment as she turned away.

Jedrzejczyk jumped in with an assault, but Letourneau was able to grab onto the clinch and survive through the end of the round.

As the second round got underway a mouse started to develop under Letourneau's right eye as she tried to time the champion's striking and counter with some hard punches of her own.

Jedrzejczyk was clearly the more active fighter throughout the second round, but Letourneau's ability to fire back with technical kickboxing kept the Polish strawweight honest and unable to put together many big combinations.

Letourneau maintained her aggressiveness going into round three, but there was no doubt that she began to slow down as Jedrzejczyk continued to put on pressure.

Jedrzejczyk began punishing Letourneau with more and more kicks as the third round ticked away and with a barrage of shots to the leg as well as a few more straight up the middle landing to the body.

Jedrzejczyk's ability to stay active while Letourneau remained flat footed gave her the opening to put together better combinations. She got more comfortable and her striking got faster and faster as the round came to an end.

By the time the fourth round got underway, Jedrzejczyk had landed 31 leg kicks, which showed by the giant welt growing on Letourneau's left lead leg.

Jedrzejczyk continued to jump in to land a few strikes and then bounced right out again and while Letourneau tried desperately to land a counter shot, she was just a beat behind the champion's speed.

Jedrzejczyk punished Letourneau repeatedly but she couldn't find the power shots to put the No. 8-ranked fighter away -- although it wasn't for a lack of effort. To her credit, Letourneau never backed down, but as the swelling on her face continued to grow it was clear she was well behind on the scorecards.

In the final two minutes, Jedrzejczyk never stopped her offensive onslaught with a series of short elbows inside with Letourneau's cheek taking the brunt of the damage.

When the fight game to an end, Jedrzejczyk was clearly the winner but she gave Letourneau a nod for being an ultra-tough opponent and sticking around for all five rounds.

The final scores came back 50-45, 49-46 and 49-46 all for the champion Joanna Jedrzejczyk.

"I said Valerie was going to be tough and hard opponent," Jedrzejczyk said after the win. "You're not always going to win easy, you know? I always want to fight to fight the best and Valerie deserved it completely. Thank you Valerie for this fight, you're tough, thank you so much."

The win marks Jedrzejczyk's second straight title defense and now she will likely face Claudia Gadelha in her next fight after the two battled to a very close decision in 2014.