According to his player page, Tom de Blok has been sent down to the West Michigan WhiteCaps on June 11. Just after a good outing in which he gave up only two runs in six innings.
It is no secret Tom struggled at the start of the season as he needed to adapt to the level. But After his poor outings on April 14 and 21 in which he gave up 6 and 7 runs respectively, he started to do better.
In the following three starts, he gave up only one run per game and his ERA dropped dramatically. But Tom hit a speed bump in May and one in June as he gave up seven and five runs in those games. But the rest of his outings he did pretty well as he gave up only two runs in each of those three games.
On Sunday vs the St. Lucie Mets, Tom pitched six innings in which he gave up two runs on two hits and two walks and struck out six, by far his best outing in which he managed to bring his ERA below 6.00 for the first time this season.
It is not clear why Tom has been sent down. Perhaps because baseball is a numbers game, perhaps because the Tigers want him to work on his pitches or mechanics. It is all up in the air.
As Tom has pitched in the Midwest League before, it should not be much of a problem for him to find his groove there.