2021 WNBA Finals -- Chronicling the Chicago Sky's and Phoenix Mercury's journeys to the champions...

The WNBA Finals matchup is set, as the Chicago Sky will face the Phoenix Mercury for the league championship beginning on Sunday. The Sky won their semifinal series 3-1 against the Connecticut Sun, while the Mercury were able to win a highly contested Game 5 against the Las Vegas Aces to punch their ticket to the Finals.

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The road to the championship round wasn't an easy one for either team, as they had to battle through injuries and other kinds of adversity during the 2021 season. Nevertheless, they persevered and are now three wins away from being crowned WNBA champions. A Finals win would make Sky forwardCandace Parkerthe hometown hero, while a victory for the Mercury'sDiana Taurasi would only strengthen her case as the league's best player of all time.

Before these stars take the floor, let's take a look at how both teams got here. No journey is unique, and that statement rings true for these squads that are WNBA Finals bound.

Chicago Sky: Peaking at the right time

There were championship expectations before the Sky even took the floor for their first game of the year. They made perhaps one of the most significant moves of the offseason, signing Parker to a two-year deal. She's a former MVP and Defensive Player of the Year who joined an already talented roster. Diamond DeShields, Allie Quigleyand Courtney Vandersloot were established stars in the association, but Parker gave the squad that championship experience it lacked in previous years -- even coach James Wade admitted that when the team signed her.

Parker's first season playing for her hometown Chicago Sky didn't start smoothly. She suffered an ankle injury in the season opener against the Washington Mystics -- and it was pretty gruesome. She missed the team's next eight games, and Chicago suffered mightily. The Sky were 1-7 during that stretch, digging themselves a hole they needed to climb out of the rest of the season.

Once Parker returned to the lineup June 9, the Sky began operating like a well-oiled machine. They rattled off a franchise-record seven straight wins, getting their record to above .500 for the first time since they won their first game. Parker's presence was essential all year, averaging 13.3 points per game along with 8.4 rebounds, 4.0 assists and 1.2 blocks per game -- but she didn't do it alone.

Kahleah Copper was an offensive spark the entire season, leading the Sky in points per game (14.4) and field goal percentage (45.9). Vandersloot was sensational in orchestrating the offense, averaging 8.6 assists per game this year. DeShields did a little bit of everything, ranking fourth on the team with 11.3 points per game and second in steals with 38. This trio played all 32 games this year, which was critical to helping Chicago stay afloat as others battled injuries -- including Parker, who reinjured her ankle in an 80-76 loss to the Dallas Wings on Aug. 17 and missed the next game.

To put Parker's importance in perspective -- the Sky were 1-9 this season in games she didn't play and 15-7 in the contests she did participate in.

Chicago stumbled down the stretch, losing four of its last six entering the postseason. When the playoffs started, however, it was a completely different team. The Sky breezed past the first and second rounds, beating the Wings and theMinnesota Lynx by an average of 15 points per game. Now they had to overcome the top-seeded Sun, who have2021 league MVPJonquel Jones on their roster.

The semifinals were much tougher than the first two rounds, as an overtime win in Game 1 and a defeat in Game 2 had the series tied 1-1. Copper catapulted her squad to a close win in Game 3 with a 26-point outing, setting up an ultimately series-clinching Game 4 in Chicago. With a chance to take her team to the Finals, Parker put on an MVP-caliber performance.

She dropped 17 points, grabbed nine rebounds and dished the ball out for eight assists. She also was a pest on defense, recording two blocks and two steals. Copper chipped in 18 points, and Vandersloot led the team with 19 points -- while shooting 5-for-6 from 3-point land. It was a complete team performance, and it came at the perfect time as Chicago handled Connecticut 79-69 to clinch its spot in the championship round.

This Finals trip is a bit of history for the Sky, as they are the third team to make it there after finishing the regular season with a record of .500 or worse, per ESPN Stats & Informationresearch (the 2014 Sky and the 2013 Atlanta Dream are the other two). It was a season of ups and downs, but the Sky are peaking at the right time and are three wins from winning the franchise's first championship.

What a story that would be for Parker: The hometown hero bringing her state a WNBA title -- a dream come true.

Phoenix Mercury: Grinding to the Finals

The Mercury entered the 2021 season with high expectations -- for good reason. When you have one of the greatest players of all time in Diana Taurasi, along with a dominating big in Brittney Griner and an exceptional guard in Skylar Diggins-Smith -- you are expected to have a great season. Despite the star power on the roster, the season was a challenging one for the Mercury.

Taurasi had an injury-plagued year, as she played in only seven of the Mercury's first 19 games while dealing with a fractured sternum. After returning for just three games, she then had what she called a hip pointer, which caused her to miss even more time. Her being out of the lineup prevented the team from gaining chemistry, and it showed at times on the floor.

Griner and Diggins-Smith were the constants for this team, as they were top two in points per game and assists. They also had help from Brianna Turner -- who was second on the team in blocks -- and Kia Nurse, who brings the grit and toughness that make this Mercury team so formidable. Shey Peddy played her role to perfection, chipping in on offense when needed and playing stifling defense.

Phoenix won all of its games in August -- a sign that things were starting to come together for the team. The Mercury's win streak stretched to 10 in September -- the second-longest win streak in franchise history. The average margin of victory during that span was 12.4 points, and it was believed that the team has finally found its groove.

However, a three-game losing streak at the end of the season gave considerable cause for concern entering the playoffs. What was an even bigger issue was that Taurasi was hurt again.

The 39-year-old guard has dealt with a nagging ankle injury that caused her to miss the Mercury's first-round matchup against the New York Liberty. Despite not having its veteran leader, Phoenix managed to squeak by New York thanks to 22 points from Diggins-Smith. Taurasi returned for the second round and helped her team overcome the Seattle Storm in overtime.

Now the only team standing in the Mercury's way of getting to the Finals was Las Vegas -- led by the dominant duo of A'ja Wilson and Liz Cambage. Guards Kelsey Plum and Chelsea Gray only added to the sensational talent Phoenix would face.

This 2021 semifinals series was a back-and-forth affair, with each team exerting its dominance in certain games. With the series tied 2-2 ahead of Game 5 in Vegas, the fifth-seeded Mercury needed to dig deep to reach the championship round. It was going to be difficult, as they were without Nurse, who tore her ACL early in Game 4. Phoenix's championship hopes looked bleak in the third as the Aces put together a 14-0 run.

That was until Taurasi woke up and started playing like her usual self.

The White Mamba scored 14 fourth-quarter points, carrying her team and giving the Mercury the lead on a late 3-pointer. Griner sealed the deal on the defensive end with a crucial block on Wilson. After a trying season for Taurasi, her fourth-quarter heroics helped get Phoenix back to the WNBA Finals for the first time since 2014.

But as Diggins-Smith said after the game, the Mercury aren't done yet -- they still need three more wins before they can end their season the way many expected them to at the beginning of the season: champions of the WNBA.

The Sky and the Mercury will tip off the 25th WNBA Finals on Sunday at 3 p.m. ET on ABC -- and it's expected to be a sensational series.