As the Twins explore trades to strengthen their hold on a wild-card spot, the competition is loading up.

Kansas City, which opened a big lead on the Twins in the AL Central, has dealt for Johnny Cueto and Ben Zobrist. Toronto, which trails the Twins for the second wild-card spot, has added Troy Tulowitzki. Houston, which leads the Twins for the top wild-card spot, has traded for Scott Kazmir and is involved in talks with Philadelphia for lefthander Cole Hamels.

The Twins’ challenge to reach the playoffs for the first time since 2010 is getting tougher as the transactions roll in.

“I look at it and find it interesting,” second baseman Brian Dozier said. “It’s something that can impact the second half of the season. You see a lot of moves being made, some that are eye-opening.

“We see what is going on with the Royals. They got a lot better, especially with Cueto. He’s one of the better pitchers in the league. And Ben Zobrist, who I’ve always admired as a player. They got a lot better.”

The Twins are in the market for bullpen help and could look into solving their shortstop problem. General Manager Terry Ryan and assistant GM Rob Antony have been joined this week by their top scouts and advisers as they engage teams in trade talks.

Ryan said there’s no additional pressure to make a deal since the teams they are battling for the postseason have made moves.

“All of us are trying to do something to help the ballclub,” Ryan said. “We’re no different. What other clubs do is not going to really affect us.”

Plouffe’s baby on way

The Twins placed third baseman Trevor Plouffe on the paternity leave list following Tuesday night’s 8-7 loss to the Pirates, recalling shortstop Jorge Polanco from Class AAA Rochester. Plouffe’s wife, Olivia, has been expecting the couple’s first child.

Polanco is up with the Twins for the third time in two seasons.

Shortstop roulette

Eduardo Escobar started at shortstop. Manager Paul Molitor decided to put Escobar’s glove behind ground ball-inducing righthander Mike Pelfrey.

So Danny Santana and Eduardo Nunez were on the bench.

Molitor was asked if he is sending Santana a message by not playing him.

“I’m not trying to send him a message,” Molitor said. “I’m trying to come up with the best combination on a given day. I’ve had enough conversation — that seemed to be fairly frequent — with Nunez and Esco and Danny.”

Buxton with a bat

Byron Buxton took early batting practice with a handful of teammates, a sign he’s making progress in his recovery from a sprained left thumb.

The rookie outfielder is expected to spend the week getting his swings in. By the weekend, he could join the team on the field for pregame drills.

If he has no setbacks, Buxton could head to Fort Myers, Fla., next week, to continue his recovery.

New rankings released an updated top prospects list, and Buxton retained his top ranking, with Dodgers infielder Corey Seager now second.

The Twins’ Miguel Sano moved up to fourth, and righthander Jose Berrios is at No. 26.

Lefthander Tyler Jay (76), Polanco (89) and shortstop Nick Gordon (91) round out Twins prospects in the top 100.

Righthander Alex Meyer, who struggled as a starter and is attempting to thrive as a reliever, was No. 30 to start the season but has fallen out of the top 100.