This could be written a bit more idiomatically as:

```scala
  def findClosest(centers: Array[Array[Double]], point: Array[Double]): (Int, Double) = {
    val (bestDistance, bestIndex) = centers.zipWithIndex.minBy { case (points, _) =>
      MLUtils.squaredDistance(point, points)
    }
    (bestIndex, bestDistance)
  }
```