Column with Icon baseline fixed

main.dart

import 'package:flutter/material.dart';

void main() {
  runApp(MyApp());
}

class MyApp extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      home: Scaffold(
        body: Center(
          child: MyWidget(),
        ),
      ),
    );
  }
}

class MyWidget extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return Row(
      mainAxisSize: MainAxisSize.min,
      crossAxisAlignment: CrossAxisAlignment.baseline,
      textBaseline: TextBaseline.alphabetic,
      children: [
        Column(
          mainAxisSize: MainAxisSize.min,
          verticalDirection: VerticalDirection.up, // <-- reverse direction
          children: [
            Text('17:59', style: TextStyle(fontSize: 32)), // <-- first child
            Icon(Icons.timer),
          ],
        ),
        Text('mm:ss'),
      ],
    );
  }
}