(Photo credit: Dale Zanine-Imagn Images)

The Philadelphia Union and Chicago Fire have struggled to match preseason expectations, a trend they'll try to reverse when they meet on Saturday afternoon in Chester, Pa.

Philadelphia (0-4-0, 0 points) has become the first-ever defending Supporters' Shield winner to begin the season losing four league matches.

An exodus of personnel explains some of those struggles. Striker Tai Baribo was sent to D.C. United in a cash trade, fullback Kai Wagner was sold to England's Birmingham City and center back Jakob Glesnes was traded to the Los Angeles Galaxy for allocation money.

Their replacements have yet to pick up the slack, particularly up front where strikers Bruno Damiani and Ezekiel Alladoh are still scoreless.

But Philadelphia's narrow Concacaf Champions Cup series defeat may provide hope. The Union earned a 1-1 draw in Wednesday's second leg at Mexico City's Club America (losing the series 2-1 on total goals) and threatened repeatedly for a series-changing goal in the second half.

'I'm really proud of the push,' Philadelphia manager Bradley Carnell said. 'We lost the series, but I feel today as a group, after the struggles we've had in recent times, we win as a group.'

The Fire (1-2-1, 4 points) are coming off an exceptionally frustrating 2-1 home defeat to D.C. United last Saturday.

Chicago is seeking a second consecutive postseason berth for the first time since reaching five straight postseasons from 2005-09.

The Fire conceded twice after the 84th minute, shortly after taking the lead through Hugo Cuypers' third goal and first from the penalty spot.

'After watching the video, it's actually one of those games where the performance wasn't as bad as you originally think,' Fire manager Gregg Berhalter said. 'There were probably four instances when we were vulnerable from D.C., and after that they had nothing in the game. And for us, we're a pass away from scoring multiple goals if the pass is the right weight. We had some really good advantages inside the penalty box that we didn't capitalize on.'

Philip Zinckernagel still is seeking his first goal of the season after he had 15 in his inaugural MLS campaign with Chicago.

--Field Level Media