ST. LOUIS – This is not what the Cubs wanted to see.

The Cubs entered play Sunday night having gone 24-12 since getting swept out of St. Louis in the first weekend of May.

They were feeling good about themselves, starting to get their mojo back and playing more like the team everybody expected.

And then Javy Baez took a 90 mph fastball off the left elbow Sunday night.

In the third inning of the series finale against the Cardinals as the Cubs looked for a sweep, Jack Flaherty hit Baez with a two-seam fastball. It forced the Cubs infielder to jump around in pain and then collapse to the grass about 15 feet away from home plate as Cubs trainers looked at him.

After a couple minute delay, Baez was led off the field and Addison Russell came in off the bench to replace him at first base.

The 25-year-old was in the midst of a breakout season for the Cubs, sitting 5th in the National League with 46 RBI and on pace for a near 30-30 seaosn (33 homers, 29 stolen bases). 

He had slowed a bit (.175 average, .502 OPS in June) but still gives the Cubs so much energy and versatility on a daily basis with his ability to move around the infield and lineup.

If the Cubs are going to be without Baez for any length of time, it could be a huge blow to a team that was just hitting its stride.