KANSAS CITY, Mo. -- Raul Mondesi celebrates his 21st birthday Wednesday and almost certainly will be in the Kansas City Royals lineup for the season series finale against the Los Angeles Angels.

The 2015 World Series champion Royals should also celebrate that they won't have to play the Angels again this year after Wednesday. They are 0-5 against the Anaheim club. The Royals won five of six last year from the Angels and swept the Angels in the 2014 ALDS, but this is a different club.

The Royals want to take an extended look at Mondesi, who was their top prospect in the minors, the rest of the season.

"Time to bring him up," Royals manager Ned Yost said. "We've been getting spotty offensive production out of that second base spot. You know he's a tremendously rangy kid. He has tremendous range, strong arm, good athletic instincts."

Entering the game Tuesday, the Royals had started three different players at second base -- Omar Infante, 38 games, Whit Merrifield, 38, and Christian Colon, 22. They had combined for a .629 on-base-plus-slugging percentage, which ranked last in the majors. They hit .247 with 20 doubles, two triples and two home runs with 29 RBIs in the first 98 games. They owned a .298 on-base percentage and a .331 slugging percentage.

If the Royals had not acquired Ben Zobrist at the trading deadline last July, they probably would not have won the World Series. Zobrist, however, bolted for the Chicago Cubs after the season.

While Mondesi played mostly shortstop in the minors, he will play primarily second base the remainder of the season with Alcides Escobar remaining at shortstop.

"He's a guy that's going to be part of our organization for years and years to come," Yost said. "He's just beginning his tenure. We feel like he's ready and we want him to come up and get some valuable experience."

The Royals will start left-hander Danny Duffy for the series finale Wednesday. Duffy has been the Royals most dependable starter lately, winning his past five decisions after starting the year in the bullpen.

In his past 36 innings, he has struck out 34 and walked only four. His 8.50 strikeouts-to-walks ratio since June 27 ranks the best in the American League.

The Angels will counter with right-hander Matt Shoemaker, who is 5-10 with a 3.99 ERA. He has made seven starts this season when he has allowed two runs or less without getting a win. That includes his prior start, yielding two runs on five hits and one walk with five strikeouts in a 6-2 loss at Houston.

Left-hander Tyler Skaggs was impressive in his first big league start since July 31, 2014, and undergoing Tommy John surgery. He threw seven scoreless innings and allowed three singles as the Angels routed the Royals 13-0. Skaggs threw only 88 pitches, 63 for strikes.

"He had seven strong innings and (was) very pitch-efficient," Angels manager Mike Scioscia said.

The Angels can only imagine what a healthy Skaggs would have meant to their rotation for the past 18 months.

"It was a long one, to say the least," Skaggs said of the rehabilitation process. "There were a lot of trials and tribulations. I think it's made me stronger mentally. I'm looking forward to the rest of the season."