(Photo credit: Joe Rondone/The Republic / USA TODAY NETWORK via Imagn Images)

Arizona veteran right-hander Merrill Kelly will take the mound for what could be the final time with the Diamondbacks when he opposes Pirates left-hander Andrew Heaney on Saturday night in Pittsburgh.

As the uncertainty that comes with the final days before the July 31 trade deadline intensifies, Kelly is among the players who could draw the most interest from contending clubs should Arizona become a seller instead of a buyer in the coming days.

The Diamondbacks, who snapped a three-game losing streak on Friday with a 1-0 victory in 11 innings over the Pirates, aren't out of the postseason picture. But Arizona already has made one trade, which hints at the team looking more toward its long-term future when it dealt first baseman Josh Naylor on Thursday to the Seattle Mariners for two pitching prospects.

Kelly (9-5, 3.32 ERA) is set to become a free agent at the end of the season, as are several key Diamondbacks, including starting pitcher Zac Gallen and third baseman Eugenio Suarez, who drove in the winning run on Friday.

'I feel like it's a little too early for a reaction,' Kelly said after the Naylor trade. 'You know, it's just part of the business, part of where we're at. Obviously, there's been a million speculations about what we're doing. I think that [Thursday] is probably a signal, as far as you know what route we're taking, but you never know. We'll see what the front office has in store for us over the next couple days.'

Kelly, who has pitched all seven of his major league seasons for Arizona, is enjoying one of his better and more durable seasons, making 21 starts.

He has picked up wins in his past two starts. On Sunday in a 5-3 defeat of the St. Louis Cardinals, Kelly gave up two runs on three hits while striking out five. He issued four walks, however, just as he did July 13 when he beat the Los Angeles Angels 5-1.

Kelly is 3-0 with a 3.68 ERA in four career starts against the Pirates but did not face them when the teams met this season in late May in Arizona. The Pirates won two of three.

On Friday, the Pirates saw their three-game winning streak snapped as they were held to one hit -- a second-inning triple from veteran Tommy Pham -- over 11 innings.

Unlike the Diamondbacks, the Pirates are certain to be sellers if they make any trades in the next week.

Starting pitching is one of their biggest commodities.

Heaney, who is in his 12th season in the majors, could be a potential trade piece because he is on an expiring contract. But Heaney (4-9, 5.03) has struggled of late and is coming off one of his worst outings of the season where he matched a season high with seven runs allowed on nine hits and two walks in a 7-2 loss to the Chicago White Sox on Sunday.

Heaney faced the Diamondbacks earlier this season and did not fare well. He allowed five runs on eight hits, including two home runs, walked three and struck out two over five innings in a 5-0 loss on May 26. For his career, Heaney is 1-1 with an 8.25 ERA in three career appearances (two starts) against Arizona.

'When you fall behind, you don't have much to get guys out with,' he said after the loss. 'I guess, narrow margin of error. I've got to go make better pitches.'

--Field Level Media