Michael Clarke has broken new ground for skippers of Australia's cricket team as he and wife Kyly were were involved in the ceremonial first pitch at a Major League Baseball game in St Louis.

Followers of the Clarkes on social media will know the pair are vacationing in the United States, including a stop at Disneyland earlier in the week where the skipper lamented mixing too many hot dogs with a turn on a rollercoaster.

In St Louis to develop a range of cricket-based mitts modeled on the traditional baseball glove, the Australia skipper was invited onto the field at Busch Stadium ahead of the match against the Chicago Cubs.

Clarke took up position at home plate as catcher, a spot perhaps more suited to Brad Haddin, while his wife threw from the pitcher's mound in the pre-game tradition.

Cricket's links with baseball have grown closer than ever in recent times. The MLB held its season-opening series between the LA Dodgers and Arizona Diamondbacks at the SCG last month, a move that cause controversy with cricket purists after it forced the NSW Blues to host the Bupa Sheffield Shield Final at Canberra's Manuka Oval.

At the same time, Clarke revealed he had signed a sponsorship deal with baseball mitt manufacturer Rawlings.

Quick Single: Clarke signs up to baseball deal

Part of that deal was for Clarke to travel to Rawlings headquarters to help with the design of a specialised baseball mitt that could be used by cricket coaches for training purposes, as well as a version of the finger gloves the Australia skipper wears during catching practice.

The Australia cricket team has had a long relationship with American fielding specialist Mike Young, and he was the first to introduce the use of baseball mitts to cricket coaching.